1. Introduction
What grounds the epistemic power of perceptual experience? A straightforward phenomenalist answer is that perceptual experience has epistemic power in virtue of having a distinctive presentational phenomenology shared by good and bad casesFootnote 1 of perpetual experience (Tolhurst Reference Tolhurst1998; Pryor Reference Pryor2000; Heck Reference Heck2000; Huemer Reference Huemer2001; Tucker Reference Tucker2010; Chudnoff Reference Chudnoff, Miguens and Preyer2012; Bengson Reference Bengson2015; Smithies Reference Smithies2019; Berghofer Reference Berghofer2020; Koksvik Reference Koksvik2020). However, a rising resistance against phenomenalism denies the sufficiency or even the necessity of phenomenal consciousness for perceptual justification (Ghijsen Reference Ghijsen2014; Berger, Nanay, and Quilty-Dunn Reference Berger, Nanay and Quilty-Dunn2018; Berger Reference Berger2020; Teng Reference Teng2018, Reference Teng2024).
Contra both phenomenalists and anti-phenomenalists, I shall defend the following thesis in this paper:
Phenomenal Presentation: The epistemic power of perceptual experience is grounded in its presentational property that is (i) uniquely possessed by the experience in the good case and (ii) essentially a phenomenal property.
The disjunctivist intuition I would like to convey in defending phenomenal presentation thesis is as follows. Instead of analysing epistemic powers of good cases as some kind of epistemic bonus added to the basic defeasible phenomenal force possessed by both good and bad cases, we should take the phenomenal force exhibited by the bad cases to be dependent on (and presumably downgraded with respect to) the basic conclusive presentational force of the good cases. Relations between presentation, phenomenology, and epistemic power are more complicated than phenomenalists usually specify. That said, presentational force is essentially a type of phenomenal force and indeed the most powerful one.
Two clarificatory remarks are in order before I proceed.
First, by ‘the epistemic power of perception’, I mean a property of perception that renders it able to provide the subject with evidential justification for believing propositions about external world. I shall, consequently, focus on what grounds the evidential status of perception with respect to the content of perceptual belief (propositional justification) rather than doxastic justification understood as a property of beliefs based on perceptual evidence. Note, however, that, because doxastic justification is standardly taken to be a matter of propositional justification and proper basing, considerations about the evidential status of perception have an immediate bearing on doxastic perceptual justification theories.
Second, presentational phenomenology is most often discussed in the context of so-called immediate (or non-inferential) perceptual justification. In this paper, I do not explicitly generalise my account to non-immediate types of perceptual justification. Nonetheless, the phenomenal presentation thesis concerns the epistemic power of perceptual experience as such and not only the epistemic power to immediately justify beliefs. What I say in this paper might then have a bearing on all the types of evidential support that perceptual experience provides.
My plan for this paper is as follows. In §2, I set the ground for my argument by elaborating on the phenomenalist account of presentational phenomenology. In §3, I argue (against phenomenalism) for the first part of the phenomenal presentation thesis: (i) perceptual experience’s epistemic power is grounded in instances of a presentational property possessed by perceptual experience in the good, but not in the bad case. In §4, I argue (against anti-phenomenalists) for the second part of the phenomenal presentation thesis: (ii) presentational property is essentially a phenomenal property. In §5, I address some potential objections to the phenomenal presentation thesis. §6 concludes.
2. Presentational phenomenology
Phenomenalism about perceptual justification, broadly construed, is a view that perceptual phenomenology is necessary for the epistemic power of perceptual experience. However, actual phenomenalists usually endorse a more specific claim, namely:
Presentational Phenomenology: perceptual experience has its epistemic power in virtue of having presentational phenomenology in good and bad cases.Footnote 2
Some authors have gestured towards the purported meaning of presentational phenomenology by saying that perceptual experience not only represents the world to be in a certain way but also presents the subject with the world or reveals how things are (Husserl Reference Husserl2001: 137; Tolhurst Reference Tolhurst1998: 298–299; Foster Reference Foster2000: 12; Bengson Reference Bengson2015: 716). Despite alluding to a truly significant epistemic feature of perception, verbalisations of this kind are rather obscure. ‘Presentation’, ‘revelation’, or ‘being present in propria persona’ are per se only suggestive metaphors. On the level of explicit formulation, they give us little more than the term ‘presentational phenomenology’.
A natural way to develop the idea that presentational phenomenology consists in something more than just having representational content is to follow the content/force distinction. We can then cash out presentational phenomenology in terms of perceptual experience’s attitudinative aspects. For example, according to Heck, presentational phenomenology is a matter of representing the world with assertive force (Reference Sturgeon2000: 508–509). For Tucker, in contrast, presentational phenomenology ‘assures’ or ‘recommends’ its content as true (Reference Tucker2010: 530). This putative feature would be just like the assertoric force involved in judgement.
Despite the above, there are important reasons to avoid construing presentational phenomenology in terms of the assertoric force. As Smithies (Reference Smithies2019: 93–95) notes, being perceptually presented with some object and making a judgement have obviously different phenomenologies. Plausibly, this difference does not only come from the potential difference between the content of perception and the content of occurrent belief. Moreover, presentational phenomenology is intended to explain why perceptual presentation is evidentially basic (i.e. why it need not be evidence-based to constitute evidence for perceptual belief). However, not all perceptual beliefs are evidentially basic in this sense, even if they represent their contents with assertoric force.
Another reason why the force account of presentational phenomenology appears unpromising is that it strongly suggests an analysis of perceptual experience in terms of propositional attitudes. The content-force distinction has been widely employed in speech act theory to analyse the different types of actions a subject can make with the same propositional content, for instance: asserting, asking, entertaining, etc. (see Recanati Reference Recanati2013; Green Reference Green and Zalta2007). Schroeder (Reference Schroeder2006) has put forward a closely related analysis of propositional attitudes (namely mental states such as belief or desire). It is, then, natural to interpret a propositional attitude as a relation of representing with some force (the relation between subject and proposition).
When applied to perceptual experience, this suggests that perceptual experience is a kind of attitude towards perceptual content. I find this deeply problematic for reasons that various authors have elaborated (e.g. Crane Reference Crane2009; Brewer Reference Brewer2011). In general, both perceptual experience’s transparency with respect to the represented environment and the role experience plays in fixing the singular terms contained in propositional contents strongly suggest that perceptual experience is a different kind of mental state from a belief, for example. This is not to say that perceptual experience is not essentially representational. I would like to keep my argument in this paper open to the representationalist account of perceptual experience.Footnote 3
For the sake of brevity, representationalism can sometimes be spelled out in terms of a subject being related to a proposition more-or-less accurately expressing perception’s representational content. Literally speaking, perceptual presentation is, however, not a matter of asserting proposition or representing perceptual content as accurate. It is, instead, a matter of representing or presenting mind-independent particulars or states of affairs in a specific and direct way.Footnote 4
Hence, a natural alternative for force-account is to attempt to account for presentational phenomenology in terms of the content (rather than the attitude) representing both mind-independent objects and the purported presentational relation to them. Some have argued, for example, that perceptual experience has presentational phenomenology if it perceptually seems to a subject that he or she is visually aware of the object that is a truth-maker for the relevant perceptual content (Chudnoff Reference Chudnoff, Miguens and Preyer2012; see also Huemer Reference Huemer2001: 778; Berghofer Reference Berghofer2020). For instance, in S’s perceptual experience with presentational phenomenology regarding the content that there is a table in front of S, it seems to S that there is a table in front of S (= empirical content p) and it seems to S that S is aware of that table (= the truth maker of p).
Harrison (Reference Harrison2019) formulated the following dilemma for this account: Either it entails that the subject seems to be aware of the object as a truth-maker or it does not (he or she perceptually represents the object as the truth-maker of perceptual content or he or she does not). On the first horn, this account leads to the overintellectualisation of perception by suggesting that it operates with the concept of a truth-maker. On the second horn, it is unclear how seeming to be aware of the object yields a subject with immediate justification regarding the empirical proposition if perceptual experience is silent about the truth-making relation between the object’s existence and the empirical content’s epistemic status.
I agree that it is highly unlikely that perceptual experience (re)presents the subject as standing in a relation of awareness to the truth-makers of perceptual beliefs. However, I think that the second horn of Harrison’s dilemma can be avoided if we modify Chudnoff’s account of how perceptual presentation manifests at the level of perceptual phenomenology. I shall say more about this in §4, where I provide my preferred account of perceptual presentation. For now, let me add a last general observation about phenomenalists’ construal of presentational phenomenology.
Presentational phenomenology is not factive in the sense that having an experience with it does not entail that apparently presented objects exist (or that apparently presented states of affairs obtain). Phenomenalists allow non-presentational states such as hallucinations to have presentational phenomenology despite not presenting the subject with an object or fact (Huemer Reference Huemer2001: 58; Smithies Reference Smithies2019: 94; Berghofer Reference Berghofer2020: 175). Anti-phenomenalists also argue that some presentational states might not have presentational phenomenology (as in the ‘perky effect’, where a subject believes that he or she is hallucinating when he or she is actually perceiving [Ghijsen Reference Ghijsen2014]).
Depending on how phenomenalists understand the presentational aspect of presentational phenomenology, the non-factiveness of presentational phenomenology might be expressed in different ways. If possessing a presentational property is a matter of accurate perceptual representation, for instance, then the phenomenal content of experience with presentational phenomenology might not be true (despite experience attaching assertive force to the content). Alternatively, if the presentation is a matter of being aware that the object is a truth-maker for the perceptual content, then experience with presentational phenomenology might not render the subject aware of the represented object (despite it seeming in the experience that he or she is aware of that object). One way or another, having experience with presentational phenomenology does not entail that subject is in fact presented with the apparent object of presentation.
I shall return to the question of how to account for a presentational property in §4. For now, we can say that presentational phenomenology (as phenomenalists construe it) is presentational only to the extent that it non-factively appears (feels or seems) to a subject having experience with presentational phenomenology as if he or she is presented with some object. According to standard phenomenalists, presentational phenomenology is, in general, the non-factive appearance (seeming or feeling) of perceptual presentation. Call the phenomenal property that constitutes presentation’s non-factive appearance the ‘apparent presentational property’.
In the next section, I argue that the phenomenal power of experience with an apparent presentational property is grounded in instances of a presentational property.
3. Presentational grounds of phenomenal force
I contend that the explanation for experience’s epistemic power solely in terms of an apparent presentational property (presentational phenomenology) is at best incomplete and at worst false. Apparent presentational presentation is asymmetrically dependent on perceptual presentation. Thus, whatever epistemic power experience possesses in virtue of being apparently presentational, it more fundamentally possesses epistemic power in virtue of good cases instantiating a presentational property.
What is crucial for my argument is that the asymmetric explanatory dependence of an apparent presentational property on a presentational property is inherited by the epistemic power of the apparent presentational property. According to dogmatists, the epistemic power of the apparently presentational property can prima facie and immediately justify empirical beliefs. This prima facie status of perceptual evidence reflects the non-factive character of seeming involved in presentational phenomenology. If, however, we grant a subject with the presentational phenomenology to possess prima facie evidence for an empirical proposition, then this is because it appears to her as if her experience is presentational. This point is a conditional one: if we agree with dogmatists about experiential justification, then the most natural explanation for the prima facie epistemic power of non-factive presentational phenomenology is in terms of factive evidence provided by the relevant perceptual presentation. Hence, my claim is not that presentational phenomenology thesis is necessarily wrong, but rather presentational phenomenology is a partial and less fundamental ground for epistemic power than instances of the presentational property.
Here is an outline of an argument to this effect:
The presentational ground argument
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Metaphysical Dependence: Perceptual experience E 1 is apparently presentational in virtue of E 2 being presentational.
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Apparent Presentational Ground: Perceptual experience E 1 possesses epistemic power (at least partly) in virtue of E 1 being apparently presentational.
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Presentational Ground: Perceptual experience E 1 possesses epistemic power (at least partly) in virtue of E 2 being presentational.
This argument is valid if the relation referred to by the ‘in virtue of’ clause is transitive. Standardly, ‘in virtue of’ refers to a grounding relation. There is, however, debate about whether grounding is transitive.Footnote 5 I do not have scope here to go into the details of this debate. In general, following Litland (Reference Litland2013, Reference Litland2015), I assume that grounding as a metaphysical explanation is transitive.Footnote 6 This assumption is plausible in light of considerations concerning the completeness of metaphysical explanation. The full explanation cannot terminate downwards to the fact ψ, which only helps to ground explained fact ϕ. It must terminate on the ultimate ground relevant for the explanation in question. The transitivity of metaphysical explanation allows more fundamental explanantia to be explanantia of the same explanandum figuring on top of an explanatory structure.
I take the presentational phenomenology thesis and phenomenal presentation thesis to be theses explaining the epistemic power of experience. Thus, in-virtue-of relation underpinning my argument’s structure appears to be transitive. Let me now offer support for my argument’s premises.
3.1. Metaphysical dependence Footnote 7
Metaphysical dependence is supported by the following observation. We cannot explain the fact that experience instantiates apparently presentational properties without considering instances of presentational properties. This is because it cannot appear to you as if you are presented with α if your phenomenology is not related to the property of being presented with α. This relation might be construed in different ways. For instance, the relevant phenomenology might be related to the presentational cases by having representational content that is of the same type as experience with a presentational property (Schellenberg Reference Schellenberg2018, Ch. 4). Or, as some austere relationalists prefer to put it, the way that it is like for you to have an experience with an apparent presentational property might be subjectively indistinguishable from the way that it is like for you to be presented with α (Martin Reference Martin2004, Reference Martin, Szabó Gendler and Hawthorne2006). In any case, one cannot explain what it is like for experience to appear to be presentational (e.g. by having the same type of content or relation of subjective indistinguishability) without appealing to an instance of the presentational property.
However, the relevant dependence is asymmetric. Instances of the presentational property are not explanatorily dependent on instances of the apparent presentational property (at least when the presentational property is construed in accordance with standard phenomenalist theories, i.e., as the accuracy of perceptual content or the relational property of being perceptually aware). If the perceptual presentation is just a matter of phenomenal content being true, then nothing in the representationalist theories of phenomenal content suggests that accuracy per se requires the subject to instantiate apparent phenomenal properties. According to these theories, apparent representational properties reside in the presentational non-factive feeling with which experience represents its content but not in the truth of that content. It is irrelevant for the accuracy of perceptual representation that it non-factively seems to the subject that the content is true.
The irrelevance of presentational phenomenology for presentation-as-awareness is less obvious because the concept of awareness is prima facie closely connected to the notion of consciousness. If – as Dretske (Reference Dretske, Szabó Gendler and Hawthorne2006), for example, suggests – perceptual awareness is perceptual consciousness, then being perceptually presented with some object would entail instantiating conscious presentational properties. However, as Silva (Reference Silva, Sylvan, Sosa, Dancy and Steupforthcoming) notes, the meaning of ‘awareness’ and ‘consciousness’ diverges in both ordinary and philosophical language. Most importantly, awareness is the most general form of cognitive availability that phenomenally non-conscious beings can enjoy. Chalmers (Reference Chalmers1996) has, likewise, suggested that ‘awareness’ refers to access-consciousness (the psychological or functional notion of consciousness as availability) rather than phenomenal consciousness (consciousness as described on the personal level). It was argued that there are empirical cases of phenomenal consciousness without access-consciousness (Block’s Reference Block2011 ‘overflow’ cases) and cases of access-consciousness without phenomenal consciousness (e.g. blindsight). Regardless of whether or not these arguments are sound, it is not a priori true that perceptual awareness (i.e. access-consciousness) requires phenomenal consciousness and even less presentational phenomenology.
Even if we agree that presentation is essentially a phenomenally conscious relation to objects of perception, this does not mean that presentational phenomenology is essential for perceptual presentation. Suppose for a moment that presentation is essentially a phenomenal property. It does not follow from this assumption that the phenomenology essentially involved in perceptual presentation is such that it necessarily seems to the subject that he or she is presented with the object when he or she instantiates the presentational phenomenal property. Whatever it feels like for the subject to instantiate presentational property, the resulting experience would be necessarily factive. In contrast, as we have seen in §2, presentational phenomenology is not factive. This proves that the presentational phenomenology is not identical with the phenomenology of presentation (even if they are subjectively indistinguishable). Whether the presentational property is necessarily phenomenal is a separate question, one that I shall address in §4.
3.2. Apparent presentational ground
Let me now turn to the second premise in my argument (the apparent presentational ground). Given that my argument primarily targets phenomenalists who accept the presentational phenomenology thesis, I see little need to support apparent presentational ground.
But, what if the presentational phenomenology thesis is simply wrong rather than an incomplete explanation of experience’s epistemic power? Well, rejecting presentational phenomenology thesis undermines the presentational ground argument but does not necessarily undermine the conclusion of that argument. We would then need a separate argument for presentational ground thesis, one that does not appeal to non-factive presentational phenomenology. I shall provide materials for this kind of argument in §4 and develop it in §5 (where I address anti-phenomenalist objections).
This is a good point at which to conciliate those who have a strong internalist intuition that victims of new evil demons (introspectively indistinguishable subjects with largely false perceptual beliefs) are justified in their (false) perceptual beliefs. My argument thus far is fully compatible with this intuition. If Apparent Presentational Ground is true, and – as internalists suggest – the experiences of victims of new evil demons are apparently presentational, then such victims have justification for their beliefs. What I would like to establish by means of my argument in this section is the claim about the presentational grounds of that epistemic power of perceptual experience. I do not intend to deprive victims of new evil demons of experiential evidence. In other words, my point in this section is that if internalists are right about the epistemic situation of such victims, it is so only because we are able to explain the epistemic power of victims’ experiences in terms of properties instantiated by subjects in the good case.
This completes my defence of the first part of the phenomenal presentation thesis against phenomenalists. I now turn to the second part by arguing that epistemic power’s presentational ground is essentially a phenomenal property.
4. The phenomenality of perceptual presentation
The dialectics of my argument in the previous section seem to support anti-phenomenalist intuitions. More specifically, my discussion of asymmetric metaphysical dependence between good and bad cases of perceptual experience involves the following observation: from the conceptual point of view, the apparent presentational property involved in presentational phenomenology is neither necessary nor sufficient for a subject instantiating the presentational property in the good case. Thus, it seems that, according to the presentational ground thesis, phenomenal consciousness plays no role in explaining epistemic power of perceptual experience.
Note that I have argued so far that epistemic power is grounded more fundamentally in the presentational, rather than the apparently presentational, property. I did not say that the presentational property is not essentially a phenomenal property.
In this section, I shall defend the claim that the presentational property is essentially a phenomenal property. If accuracy or awareness does not essentially involve phenomenal consciousness, then my understanding of presentation must go beyond the standard phenomenalist account of presentation in terms of accurate perceptual representation or awareness. Indeed, my argument for essential phenomenalism about perceptual presentation is based on the premise that perceptual presentation has a distinctive feature beyond accuracy or generic awareness and that this distinctive feature is phenomenal. The basic structure of my argument is as follows:
The phenomenal presence argument
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Presence: Perceptual presentation is identical to making mind-independent particulars present to the subject’s consciousness.
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Phenomenality: Presence for the subject’s consciousness essentially involves phenomenal consciousness on the side of the subject.
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Phenomenal presence: The presentational property is essentially phenomenal.
The argument is valid because it fits the syntactic entailment schema (x = y, yRz ⊢ xRz). Let me elaborate on the premises in turn.
4.1. Presence
The first premise introduces the notion of ‘presence’, which, at first pass, does not seem to be especially useful. This is for two reasons: it seems to be a tautological and hence non-informative elaboration of the notion of ‘presentation’ and it seems to be a rather vague metaphor. I think that both my argument and indeed all phenomenalist intuitions hang on a recognition of the significance and distinctiveness of perceptual presence. I should, therefore, try to make clear what I mean by ‘presence’ and why it is more explicit about the distinctive feature of perceptual experience than the term ‘presentation’.
At a first approximation, presence to a subject’s consciousness is a robust form of direct contact with reality—the unmediated manifestation of what exists out there for the subject’s consciousness.Footnote 8 Even if factive and containing singular elements, propositional attitudes do not present things in this way. This is also the case if they possess a distinctive cognitive phenomenology and even if they relate subjects to reality in different ways. Belief or even knowledge that the cat is on the mat does not bring me into direct contact with either the state of affairs that the cat is on the mat or the cat itself. Propositional attitudes such as belief and knowledge do not make things present to me, at least not in the way that perception does. And, this distinctive sense of perceptual presence is what I am trying to pin down here.
Both perceptual mode of presentation and the ontological status of things made present in perception are crucial to the nature of presence. Things that do not exist as mind-independent particulars cannot be present. The experienced and existing cat on the mat is present to me in perception. However, this is not true of a ‘hallucinated’ cat or non-obtaining states of affairs constituting truth conditions for hallucinatory content. This is the case even if the hallucination possesses an apparent presentational property.
Ranalli (Reference Ranalli and Kriegel2021) has argued that presence has distinct epistemic value beyond truth and justification. However, presence still explains perception’s evidential status, even if it is of epistemic value distinct from justification. This is because perceptual presence is of the highest epistemic value when it comes to both quality of access to the grounds of perceptual knowledge (direct contact with reality) and quality of evidence (evidence being factive). Even if not explicitly represented by the experience or the subject as such, presence is the most epistemically robust form of awareness of things that stand in a relation of truth-making (Chudnoff Reference Chudnoff, Miguens and Preyer2012) or ‘alethic necessitation’ (Anaya Reference Anaya2021) to the propositional contents of beliefs based on that experience. The epistemic value of the presence of particulars being truth-makers explains the epistemic power of perceptual experience, even if a subject presented with truth-makers does not explicitly represent them as such.
Presence, however, cannot be analysed away in terms of presentation understood as veridical representation or awareness (see §3.2 above). It is something more than accurately representing the world or just being somehow aware of worldly entities in the generic sense of the word. That said, phrases such as ‘direct contact with reality’ or ‘unmediated manifestation of existing objects’ do not aim to provide an analysis but rather a characterisation of the notion of presence. Such characterisations are not capable of providing us with new knowledge. Instead, they make an understanding of the perceptual experience that we already have explicit. This way of characterising phenomenal presence is similar to Smithies method of explaining the notion of presentational force:
Presentational force is a kind of phenomenal character that we know ostensively by introspecting perceptual experience and contrasting it with other experiences. It is the kind of phenomenal character that your experience has when you perceive things, and when you hallucinate them, but not when you merely visualize or make judgments about things. To rephrase what Pryor says, it is the kind of phenomenal character that your experience has when you can just see that hands are present. (Smithies Reference Smithies2019: 94)
I would like to adopt and modify this method to provide a better grip on the notion of perceptual presence. First of all, experiences that might serve as introspectively accessible examples of the relevant perceptual presentation cannot just be the same examples as those specified in Smithies’ ostensive definition of presentational phenomenology. This is because presentation (in the sense of making things present) is factive while presentational phenomenology is not. A hallucination might have an apparent presentational property, but it does not make mind-independent particulars present to us.Footnote 9
A natural reaction is to say that the required example of introspectively ostensible presentation is not provided by perceptual experience irrespective of being good or bad, but rather only by good cases (namely, phenomenally conscious perceptions). This proposal, however, faces an immediate objection from the subjective indistinguishability of good and bad cases. It is, for instance, possible to have a hallucination that is subjectively indistinguishable from conscious perception (i.e. shares a presentational phenomenology with perception). When referring to two experiences’ subjective indistinguishability, I mean that a subject cannot tell them apart based solely on introspection of how things appear to her in that experience. Things appearing to her as if they are P explains experience’s subjective indistinguishability (in contrast to, e.g., indistinguishability resulting from the subject’s lack of attention).Footnote 10 Thus, some experiences might misleadingly appear to make things present to subject consciousness. A subject cannot tell them apart based solely on their phenomenal character. If it is possible – and I see no reason arising from my argument to deny this – to be massively mislead by merely apparently presentational experiences, then new evil demon victims are possible entities. This seems to severely restrict the introspective ways of knowing a presentational property.
For this reason, I accept that introspection alone is insufficient to single out and thus ‘ostensively define’ perceptual presence. But this kind of reasonable modesty about introspective self-knowledge must be understood within limits defined by subjective indistinguishability. Perceptual presence is not luminous, at least not in the sense suggested by some epistemological disjunctivists (e.g. McDowell Reference McDowell, Doyle, Milbrun and Pritchard2019; Logue Reference Logue, Gersel, Jensen, Thaning and Overgaard2018; de Bruijn Reference De Bruijn2022). Whether your experience has a presentational property or rather a merely apparent presentational property, you cannot know just by introspecting how things appear to you in perceptual experience (even less by just having that experience). This does not mean, however, that you cannot introspectively attend presentational property. If everything goes well, then this kind of introspection is a paradigmatic pathway to self-awareness of phenomenal presence.
I contend that our grasp of the perceptual presence concept has sources other than introspection, namely a tacit understanding of the nature of perceptual experience and its presentational phenomenology that goes beyond our introspective discrimination abilities. Together with introspectively attending presentational property, explicating this understanding suffices to grasp the notion of phenomenal presence.
When talking about explicating an understanding of presentational phenomenology, I am referring to an exercise like the one I undertook in §3 when motivating the metaphysical dependence premise. Such an understanding follows the structure of the explanatory asymmetric dependence of apparent presentational properties on presentational properties. Thus, even if we cannot tell good from bad cases of perceptual experience by introspection alone, we can understand what is like to have some kind of perceptual experience with presentational phenomenology in virtue of taking perceptual experience to fundamentally be a matter of making the world present to us.
For normal adult human beings, introspection is a paradigmatic way of being aware of what it is like to have a perception with a presentational property. Nonetheless, in any given case of perceptual experience, we cannot by introspection alone rule out the possibility that this particular experience is not presentational. We cannot know just by introspecting perceptual experience that perceptual experience on any given occasion is presentational rather than merely apparently presentational. That said, we can understand (if we understand it at all) what it is like to have a perceptual experience only in light of introspectively available cases in which perception makes the world present to us. Our inability to introspectively rule out the sceptic scenario does not threaten our understanding, even if it threatens our self-knowledge. Prior to an attempt to know the nature of an experiential episode on any given occasion, our basic self-understanding of our experience as such is based on the notion of presence. I think that an explication of this basic understanding is all that we can reasonably aspire to provide when asked to explain what we mean by experience making mind-independent particulars present to us.
4.2. Phenomenality
Let me now elaborate on the second premise. What supports the claim that only phenomenally conscious states can make mind-independent particulars present to a subject?
In answering this question, I would like to put aside thought experiments involving full phenomenal zombies. Phenomenal zombies are conceivable creatures who on the functional and internal side are just like us but lack all our phenomenal properties. Intuitions about the plausibility of such creatures being presented (in the relevant sense) with things that their sensory systems ‘perceive’ might be severely biased by tacit assumptions about the connection between subjectivity and phenomenality. If phenomenal zombies are not ‘subjects’, then there is nothing to be presented to them (because there is no subject to be presented with something). I am not interested in the question of whether phenomenal zombies are subjects. Instead, I am interested in the question of whether a state presenting a creature with mind-independent particulars is necessarily phenomenally conscious (granted that it is uncontroversial whether that creature is a subject).
Hence, we should focus on cases that are neutral about the subject’s overall phenomenal consciousness, cases entailing only that the perceptual state in question is not phenomenally conscious. Classic examples that are interpreted this way are empirical cases of so-called blindsight (Weiskrantz Reference Weiskrantz1990) and its conceptual extensions super-blindsight and super-duper-blindsight (Block Reference Block1995). Blindsight is where a subject reports no visible features in at least part of the visual field owing to a neural impediment but performs reliably when prompted to undertake tasks involving perceptual information about those ‘unseen’ features. Importantly, blindsighted subjects are not disposed to form perceptual beliefs about ‘unseen’ features. When prompted to answer a question about the ‘unseen’ feature’s presence, blindsighters report that they are ‘guessing’ rather than basing their perceptual beliefs on evidence. Super-blindsighters are (at least) possible creatures just like real blindsighters but who are disposed to form spontaneously relevant perceptual beliefs based on unconscious perceptions. Super-duper-blindsighters are like super-blindsighters but are also disposed to form a metacognitive belief about the reliability of their phenomenally unconscious perceptual information.
I contend that phenomenally unconscious perceptions do not make things present to these subjects and do not provide them with perceptual evidence. This is the case regardless of the nature of the cognitive relation between blindsighters and the ‘unseen’ features and what we are inclined to say about the epistemic value of these unconscious states. In the case of blindsighters, it is relatively easy to interpret their hesitance when it comes to answering questions about the presence of relevant features in this way (Weiskrantz Reference Weiskrantz1990: 46–57).
Things are different in the case of super-blindsighters and super-duper-blindsighters. They do not hesitate to form perceptual beliefs. Their disposition to and spontaneity (or even felt confidence) in believing on the basis of an unconscious perception, however, does not support the verdict that these unconscious states make things ‘present’ to them. From the perspective of super-blind seeing or super-duper-blind seeing subjects, the felt confidence and known reliability of their perceptual capacities is more like a reliable clairvoyant’s confidence than like a confidence of subject presented with an object he or she refers to. Clairvoyants whose clairvoyance is not just a matter of stretching experience to unusually distal parts of spatiotemporal reality have no direct contact with reality, even if they can be fully confident of their doxastic states. Such clairvoyants and blindsighters do not have access to mind-independent particulars themselves. They, instead, have access to highly reliable information that, from their perspective, pops out of the (phenomenal) blue without making mind-independent particulars present.
We can press this point by facing anti-phenomenalists about perceptual presentation with the following dilemma. If blindsighters are presented with mind-independent objects in the environment, then the presence of such objects must be explainable in terms of either unconscious perceptual states or beliefs referring to these objects (if they are super-blindsighters or super-duper-blindsighters). However, neither unconscious perception nor belief can explain the contact with mind-independent particulars involved in perceptual presence.
On the first horn of the dilemma, unconscious perception can be fully characterised in terms of its functional role, the role of providing accessible information for the subject’s actions and higher-order doxastic states. Unconscious perception is ‘epistemically parasitic’, in the sense that it has no cognitive or epistemic role of its own despite its function to cause doxastic states and behaviour. If we say that unconscious states make subjects ‘unconsciously aware’ of certain things or put them in contact with the objects of cognition, then what we mean is the following: here is a chain of causal interactions that proceeds through the brain system modules we identify as ‘perceptual’ and such causal interactions correlate counterfactually with a subject’s disposition towards a certain behaviour or verbal doxastic report. Such counterfactual correlation, under the representationalist explanation of behaviour, strongly supports the view that perceptual modules not only register information but also yield cognitive systems with the sub-personal representations of environment (see Burge Reference Burge2021: 21–30). Sub-personal representations on their own, however, cannot amount to the personal-level, subjective epistemic access to evidence that is offered by presentation. Bodily movements guided by these representations do not offer subjects with the ‘presentation’ of the environment in the plausible sense of the word. If a subject – qua subject – has any form of access to these sub-personal information-carrying processes, it is only the access-consciousness offered by other, personal-level states and actions (e.g. ‘introspective guessing’ manifested in verbal reports in blindsighters, ‘tacit’ belief rationalising behaviour triggered by perception, or reported belief in super-blindsighters). And only because phenomenally unconscious subjects manifest these other, perception-based, personal-level states can we ascribe them with some sort of (parasitic) perceptual, but phenomenally unconscious, awareness of mind-independent facts. This brings me to the second horn of the dilemma.
On the second horn of the dilemma, blindsighter’s beliefs do not make mind-independent particulars present to the subject (even if they are accompanied by some sort of cognitive phenomenology). This is obvious for metacognitive beliefs. For example, a super-duper-blindsighter’s metacognitive belief that her unconscious perceptual processing is reliable might, at best, have a presentational force with respect to the proposition ‘my perceptual processing is reliable’. However, such an intuitive presentation of truth does not constitute the presence involved in a perceptual presentation of mind-independent particulars. Likewise, a perceptual belief or even perceptual knowledge spontaneously formed by super-blindsight on the basis of unconscious perception does not amount to the presence of mind-independent particulars. Knowing that the cat is on the mat does not make the cat present to me in the sense that a conscious perception of the cat on the mat does. If we do not ascribe such a presentation to the perceptual beliefs or knowledge of a phenomenally conscious perceiver, then why should we not ascribe it to super-blindsighters’ perceptual or metacognitive beliefs? It follows that if neither unconscious perceptions themselves nor personal-level states based on them present a subject with environment, then the subject without perceptual experience cannot be presented with the environment in the sense defined in §4.1.
One might object on naturalistic grounds, for instance, that what it is for a state to make something present just is to carry information. Therefore sub-personal, phenomenally unconscious perceptual processing would count as ‘presentation’. However, what it means to be presented with something is not a matter of terminological stipulation, but rather fixed by the paradigmatic cases of the phenomena in question. I take perceptual experience of mind-independent objects to be the paradigmatic case of presentation (i.e. the case that grounds our understanding of what presentation is). In other words, our grasp on what it is for a subject to have direct cognitive contact with reality is anchored in our self-understanding of our experiential, phenomenal presentation of our surroundings. Phenomenal presentation is thus an anchoring-instance of presentation in the similar sense to which, according to Kriegel (Reference Kriegel2011, ch.1) experience is an anchoring-instance of intentionality. Without a convincing argument to explain how the same conditions for presentation that are met in the anchoring, phenomenal case are also met in the non-phenomenal case, we cannot plausibly extend our experience-based understanding of presentation to sub-conscious information-processing. And, indeed, I do not see that such an argument is likely to be forthcoming.
I am open, however, to granting cognitive systems that instantiate non-experiential forms of representation to have different, perhaps more rudimentary, forms of awareness of mind-independent environment from perceptual presentation. That is, perhaps, the form of perceptual awareness available for phenomenal zombies and blindsighters. One might call it ‘presentation’ so long as it is not confused with the distinctive form of awareness essential for the phenomenal presentation of mind-independent particulars. If the debate over the nature of phenomenal consciousness might be one day resolved in favour of reductive representationalism, and the explanatory gap between those rudimentary forms of representation and perceptual experience be closed, then we would take an important step towards identifying information-carrying perceptual processes with ‘perceptual presentation’. But as long as the debate remains unresolved, I feel free to insist that perceptual experience has an important epistemic role that cannot be played by phenomenally unconscious states.
This completes my defence of the phenomenal presence argument’s premises. Taken together, the conclusions to the presentational ground argument and the phenomenal presence argument entail the phenomenal presentation thesis (perceptual experience’s epistemic power is grounded in its essentially phenomenal presentational property as uniquely possessed by an experience in the good case).
Let me now turn to some possible objections to my arguments.
5. Objections and replies
Objection 1. It is highly implausible that phenomenal presence is necessary for evidential justification. Hallucinations, for instance, are merely apparently presentational but nonetheless provide a subject with prima facie justification. Similarly, no belief makes mind-independent particulars present to the subject’s consciousness in the sense required by the phenomenal presence argument, but beliefs are capable of possessing epistemic power. If perceptual presence is not necessary for evidential justification, then perceptual presence cannot ground epistemic power given that grounding entails necessity.
Reply 1. Note that the presentational ground thesis allows for the grounding of epistemic power that holds across numerically different states. For instance, it allows for a good case of perceptual experience E 1 to ground the epistemic power of a merely apparently presentational experience E 2. This allows hallucination to have epistemic power in virtue of a numerically different state of perception being presentational. Similarly, the epistemic power of perceptual belief is grounded in perceptual experience through belief being evidentially based on an experience exhibiting epistemic power of its own. The mere fact that some mental states with epistemic power do not possess the presentational property does not speak against the necessity of presentation for epistemic power.
The real question, then, is not whether state M 2 might possess epistemic power without possessing the presentational property. It is, instead, whether it is possible for M 2’s epistemic power to not be metaphysically dependent on the presentational property of M 1. My response to this consists of two steps.
First, I would like to avoid answering the above question on such a general level and restrict myself to the perceptual evidence. I am neutral on the question of whether non-perceptual justification (e.g. justification by testimony or a priori justification) is metaphysically dependent on presentation. This move blocks any attempt to undermine claims about what grounds perception’s evidential status by simply generalising from non-perceptual cases of evidential justification.
Second, one can claim that the grounding of epistemic power perceptual evidence necessarily terminates downward on perception with the presentational property. The presentational property’s essentiality for perceptual evidence is primarily supported by considerations about the nature of the access required by all forms of evidentialism. In contrast to other possible justification-conducing factors such as reliability, evidence constitutes (or in principle might constitute) the subject’s epistemic reason for belief. The subject must have access to evidence to base her belief on it. The relevant considerations do not possess evidential status (in this sense) independent of being possessed by the subject (Schroeder Reference Schroeder2008). Therefore, what we call ‘objective evidence’ are, in fact, relevant considerations that redound on the epistemic value of belief (e.g. its truth), but properly speaking, these relevant considerations would be evidence if the subject would have access to them. Thus, we cannot explain E’s evidential status independent of E being accessible to the subject (at least in some possible scenario).
Now, phenomenal presence is the highest and explanatorily most fundamental form of access to the epistemic reasons provided by perception.Footnote 11 The idea is that, for whatever reason, we take hallucinators, blindsighters, or zombies to have access to some sorts of things that seem to function just like normal perceptual evidence, the epistemic value of non-presentational perceptions is something less valuable and derivative with respect to the access and evidence provided by experience making mind-independent particulars present for the subject. We can praise such non-presentational subjects for coherence, reliability, or even the truth of their perceptual beliefs. But, we only praise any creature for having evidentially based perceptual beliefs because we fundamentally praise perceptual beliefs for being based on the direct phenomenal presentation of a mind-independent reality.
The presence of a mind-independent reality is the perceptual access to evidence. There is no deficiency in this way of possessing perceptual evidence.Footnote 12 There is an important form of access to a mind-independent world that hallucinators and blindsighters lack, even if they share some psychological features with subjects who possess evidence in the paradigmatic sense. It is an open question whether blindsighters might possess evidence of another sort (however paradoxical it would be for unconscious perception to provide them with non-perceptual evidence).Footnote 13
Objection 2. Phenomenal consciousness is not necessary for perception’s evidential status (Berger Reference Berger2020). Having evidence is essentially a matter of having personal-level state that is causally implicated (or implicated by the rationalising explanation of) a belief’s occurrence. As is clear from cases basing belief on unconscious belief, personal-level states that play an evidential role might be unconscious (Lyons Reference Lyons2016). Thus, the perceptual presentation’s phenomenality is not necessary for perception to have epistemic power, even if that perceptual presentation is essentially phenomenal and plays an epistemically significant role.
Reply 2. I agree with Berger (Reference Berger2020) that only personal-level states can provide subjects with evidence. That said, I think that only phenomenally conscious perceptions can constitute personal-level perceptions.
Note that two of the three criteria for personal-level perception that Berger (Reference Berger2020) provides – encoding information in an egocentric way and enabling perceptual constancies – have no clear bearing on the attribution of perceptions as personal-level states.Footnote 14 In other words, they are not criteria for being a personal-level state, even if they are met by all personal-level perceptions. Representing space in an egocentric frame of reference has nothing to do with attributing that representation to the subject rather than its perceptual sub-system. This is because the ‘ego’ in ‘egocentric framework’ is not the subject rather than any other entity localised in the perceptual field’s vantage point.
Similarly, representing objects as the same despite a change of subjective perspective implies nothing about having de se content or that content referring to the subject in the sense that is relevant for being personal-level states. Another characteristic that Berger (Reference Berger2020) provides – ‘interacting with other intentional states’ – is more promising, at least if ‘interaction’ is inferential. Plausibly, being inferentially integrated with the subject’s other states is a necessary condition for being a personal-level state (see Stich Reference Stich1978). The problem is that it is not clear whether unconscious perceptions are, in fact, integrated in this way or modularly encapsulated. More importantly, inferential integration is not sufficient for being a personal-level state.
This leads us to the issue of the accessibility of a personal-level state’s content to subject consciousness. Stich (Reference Stich1978) famously argued that unconscious beliefs count as personal-level (or doxastic) states because they are accessible to verbal reporting (e.g. the subject can state whether or not he or she believes p when asked). Importantly, the previously unconscious belief becomes conscious when accessed in this way. It is highly unlikely that something of this sort occurs in cases of phenomenally unconscious perception. Blindsighters cannot report perceptual content at all. There is nothing to say in response to the question of what they see.Footnote 15 At best, they can reliably guess what there is in the blinded field. More importantly, such a guess does not yield them with conscious perception (just like accessing the content of unconscious personal-level belief makes it conscious belief). This is even clearer in the case of super-blindsighters, who are disposed to have personal-level beliefs based on unconscious perception. Yet, again, those beliefs do not make perceptual content available for verbal reporting because the content of their perceptual belief is not perception’s content.
A prima facie complication for this kind of reply is based on an independently plausible understanding of access-consciousness according to which state M is access-conscious if M is available for verbal reporting or for guiding a subject’s behaviour (Block Reference Block1995: 228). There are empirical studies on blindsighters in which subjects manifest their ability to behave in accordance with unconscious information (e.g. successfully navigating a corridor with phenomenally ‘unseen’ obstacles). The most natural explanation is that unconscious perceptual content is available to modules responsible for the subject’s motoric behaviour, even if it is not available for verbal reporting. If this broad sense of ‘access-consciousness’ is sufficient for personal-level states (see Berger and Mylopoulos Reference Berger and Mylopoulos2019), then blindsighters’ phenomenally unconscious perceptions might be personal-level states and eventually constitute evidence.
The problem is, however, that being available for a module triggering a subject’s behaviour seems to be far from sufficient for availability on the personal level, even if the triggered behaviour is, in some sense, attributable to the subject. Stich’s (Reference Stich1978) condition of personal-level states – the availability for verbal report – seems to be so apt because it targets events that typically constitute a subject’s first-person perspective and that carry an explicit representation of environment that might serve as evidence. This is not to say that only contents available for verbal report might constitute evidence. The point is rather that it is highly controversial that sub-conscious processing figures in a subject’s perspective just because it triggers behaviour. The behaviour of blindsighters, in contrast to the verbalisation of belief, does not yield any explicit representation of the environment but is rather caused by representation that is not accessible on the personal-level and cannot thus constitute a subject’s evidence.
Moreover, if information were to meet the access-condition on evidence possession by being accessible for motoric modules, then the resulting justification offered by such sub-conscious representation would be purely propositional and objective rather than possibly doxastic and subjectively available justification. E.g. the contents of super-blindsighters’ perceptual beliefs would be justified by the facts about the environment that are non-phenomenally accessible for modules responsible for belief-formation, but super-blindsighters would be unable have these facts as evidence and to evidentially base their beliefs on them. This is because epistemic basing is more than mere causing, even if the cognitive system is access-conscious of the relevant cause. A subject who bases a belief on evidence believes for an available reason constituted by that evidence. This relation of evidential support is normative rather than merely causal. The availability of reason for evidential basing requires reason to figure in an agent’s perspective. There are plausibly myriad events occurring under my skin and skull, as well as in my environment, that causally influence belief-formation processes in my mind. The occurrence of these events might even stand in some sort of relation probabilistic support to the contents of my belief. However, many of these events do not figure in my epistemic perspective and hence they cannot constitute the evidence I have.
Therefore, even if unconscious perception redounds on the epistemic status of the subject’s beliefs in many ways, it cannot constitute her evidential basis just because unconscious perception’s content can guide her behaviour or even prompt her to reliably form a belief.
This observation is clearly supported by blindsighters’ inability to form outward belief and super-blindsighters’ inability to identify the source of evidence. Super-duper blindsighters rightly identify the source of this information about environment, but, importantly, that kind of meta-cognitive bypass of perceptual experience provides no replacement for the presentation of environment, but only for self-knowledge or self-understanding based on experience-directed introspection.
Objection 3. Phenomenal consciousness is plausibly a form of mind-oriented rather than world-oriented higher-order thought. If this is the case, then it cannot contribute to perception’s epistemic power vis-à-vis empirical propositions about the external world (Berger Reference Berger2020). Phenomenal presentation is a form of phenomenal consciousness. Thus, the subject’s own mental state (rather than any worldly object) is present in her consciousness in phenomenally conscious perceptual experience. It follows that phenomenal presence is not even sufficient for the epistemic power of perceptual experience vis-à-vis empirical propositions.
Reply 3. In general, I think that higher-order theories of phenomenal consciousness face fatal problems. These problems arise from conflating the inward-oriented phenomenology of thoughts about first-order states and the outward-oriented phenomenology of perceptual experience (see Dretske Reference Dretske1993, Reference Dretske1995). Nevertheless, I think that the objection against the sufficiency of phenomenal character for a perceptual justification from higher-order theories of consciousness might be answered without undermining the higher-order theories as such.
A reply to this effect suggests that my argument for the phenomenal presentation thesis is sound, even if phenomenal presence is the joint upshot of a first-level perceptual state being inherently related to the environment and a higher-level state rendering the first-level state phenomenally conscious. This might be expressed in terms of the distinction between the qualitative and subjective aspects of phenomenal character (Kriegel Reference Kriegel2009).Footnote 16
Phenomenal presence is a matter of worldly qualities being present to the subject. The qualitative aspect (e.g. whiteness aspect of my conscious perception of a white cup) is explained in terms of properties that perception (irrespectively from being conscious) relates me to, but that qualities being phenomenally present for me is explained in terms of my higher-order state directed towards that that state with qualitative property. On this interpretation, the phenomenal consciousness essentially involved in the perceptual presence (making things present for subject) is a matter of the subject having a higher-order state about a first-level relational perception. A key intuition behind this response is that, even if essentially subjective character of phenomenology is a matter of representing one’s own mental state via a higher-order state, this does not imply that a phenomenally conscious state is phenomenally presenting one with one’s own mental state rather than the worldly properties.
Objection 4. Presentational phenomenology is produced by a separate metacognitive state rather than perceptual experience (Teng Reference Teng2023, Reference Teng2024). Metacognitive states are highly unlikely to play a role in immediate perceptual justification because we do not base our perceptual beliefs on metacognitive states (at least not in typical perceptual justification scenarios). Therefore, presentational phenomenology is not epistemically significant.
Reply 4. Teng’s arguments for identifying presentational phenomenology with metacognitive source-monitoring states are based on the assumption that presentational phenomenology is a kind of mind-directed epistemic feeling with content explicitly including first-level states (e.g. perceptual experiences). An example is a feeling with content along the following lines: ‘this is veridical perception’ or ‘this is true’, where ‘this’ refers to a perceptual state or perceptual content.
I admit that some phenomenalist formulations of presentational phenomenology invite this interpretation. However, in §2, I criticised views according to which presentational phenomenology is a matter of representing perception as accurate. In §4, I proposed an alternative method for identifying a distinctively presentational phenomenology. The upshot of my arguments in this paper is that perceptual phenomenology picks up a disjunctive class of phenomenal properties. These are either phenomenal properties essentially involved in the perception rendering mind-independent particulars present to the subject’s consciousness or subjectively indistinguishable properties possessed by merely apparently presentational perceptions.
Now, I leave it open whether this disjunction amounts to the disjunction in nature of phenomenology. Perhaps the disjunction between presentational and merely apparently presentational properties may be accounted for in terms of the same type of phenomenal properties that differentiates on introspectively inaccessible level. One way or another, there is no commitment to the idea that presentational phenomenology is some kind of epistemic mind-directed feeling, one that is about experience rather than the world. Making worldly objects present to a subject’s consciousness or yielding her with an introspectively indistinguishable phenomenology is radically different from representing perception as veridical. This solution suggests that perceptual states might exhibit presentational phenomenology even if they are deemed to be non-presentational at the metacognitive level. It, for instance, allows for ‘lucid’ hallucinations in which it feels as if one is presented with mind-independent particulars even if one knows (and in some sense feels) on a metacognitive level that one is hallucinating and not being perceptually presented with mind-independent objects.
6. Conclusion
I have done four things in this paper. First, I clarified the notion of presentational phenomenology as understood by dogmatists about perceptual justification.
Second, I presented an argument defending the claim that perceptual experience’s epistemic power is grounded in instances of a presentational property that is possessed only by good cases of perceptual experience. At that point, I did not provide any positive characterisation of perceptual presentation but rather took this term as a placeholder for the property possessed only by the good cases of perceptual experience which, when instantiated, entails the truth of perceptual belief based on how things are presented in the perception.
Third, I put forward an argument defending the claim that instantiating a presentational property essentially involves a subject’s phenomenal consciousness. This argument is based on a more positive account of perceptual presentation in terms of making things present to the subject. Taken together, these two arguments support the thesis that perceptual experience’s epistemic power is grounded in a phenomenal presentational property that is uniquely possessed by experience in the good case.
Fourth, I addressed some prima facie objections to my thesis, namely an argument from the epistemic irrelevance of phenomenal presence, an argument from the unconscious evidence, an argument from the higher-order theories of consciousness, and an argument from the metacognitive account of presentational phenomenology.
The upshot of these efforts is a moderately disjunctivist view of the epistemic power of perceptual experience. This view does not require self-knowledge of a perceptual presentation for presentational experience to provide conclusive evidence.Footnote 17 That conclusive evidence is explanatorily basic (and better) phenomenal evidence rather than just more evidence possessed in addition to the basic phenomenal evidence possessed in the good and the bad cases.Footnote 18
Acknowledgements
The author is deeply grateful for the valuable comments on the original version of the manuscript provided by the anonymous Editor and Reviewer from Episteme. The author extends special thanks to the organizers and participants of the workshop “The Epistemic Significance of Perceptual Consciousness” held on May 30-31 in Krakow, Poland. Participation in this event provided the impetus for the creation of this text. This research was funded in whole by National Science Centre, Poland, grant number 2021/40/C/HS1/00281. For the purpose of Open Access, the author has applied a CC-BY public copyright licence to any Author Accepted Manuscript (AAM) version arising from this submission.
Funding
This research was funded in whole by National Science Centre, Poland, grant number 2021/40/C/HS1/00281.
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