In this commentary we explore Knobe's ideas of moral judgments leading to moral intuitions in the context of the moral thought and moral action debate. We suggest that Knobe's primary moral judgment and the setting of a continuum with a default point is in essence a form of cultural capital, different from moral action, which is more akin to social capital.

Neural reuse theories should interest developmental psychologists because these theories can potentially illuminate the developmental relations among psychological characteristics observed across the lifespan. Characteristics that develop by exploiting pre-existing neural circuits can be thought of as developmental homologues. And, understood in this way, the homology concept that has proven valuable for evolutionary biologists can be used productively to study psychological/behavioral development.

Moral judgments often affect scientific judgments in real-world contexts, but Knobe's examples in the target article do not capture this phenomenon.

Anderson claims that the hypothesis of massive neural reuse is inconsistent with massive mental modularity. But much depends upon how each thesis is understood. We suggest that the thesis of massive modularity presented in Carruthers (2006) is consistent with the forms of neural reuse that are actually supported by the data cited, while being inconsistent with a stronger version of reuse that Anderson seems to support.

Knobe's argument rests on a way of distinguishing performance errors from the competencies that delimit our cognitive architecture. We argue that other sorts of evidence than those that he appeals to are needed to illuminate the boundaries of our folk capacities in ways that would support his conclusions.

I agree with Anderson's approach to reuse theories. My main concern is twofold. Anderson assumes certain nomological regularities in reuse phenomena that are simply conjectures supported by thin evidence. On the other hand, a biological theory of reuse is insufficient, in and of itself, to address the evaluation of particular models of cognition, such as concept empiricism or conceptual metaphor.

Neural reuse demonstrates preadaptation. In accord with Rozin (1976), the process is an increase in accessibility of an originally dedicated module. Access is a dimension that can vary from sharing by two systems to availability to all systems (conscious access). An alternate manifestation is to reproduce the genetic blueprint of a program. The major challenge is how to get a preadaptation into a “position” so that it can be selected for a new function.

Anderson's massive redeployment hypothesis (MRH) takes the grounding of meaning in sensorimotor behaviour to be a side effect of neural reuse. I suggest this grounding may play a much more fundamental role in accounting for the bootstrapping of higher-level cognition from sensorimotor behaviour. Thus, the question of when neural reuse delivers semantic inheritance is a pressing one for MRH.

Neural reuse theories suggest that, in the course of evolution, a brain structure may acquire or lose a number of cognitive uses while maintaining its cognitive workings (or low-level operations) fixed. This, in turn, suggests that homologous structures may have very different cognitive uses, while sharing the same workings. And this, essentially, is homology thinking applied to brain function.

Moral considerations and our normative expectations influence not only our judgments about intentional action or causation but also our judgments about exact probabilities and quantities. Whereas those cases support the competence theory proposed by Knobe in his paper, they remain compatible with a modular conception of the interaction between moral and nonmoral cognitive faculties in each of those domains.

In distinguishing itself from other distributed approaches to cognition, Anderson's theory of neural reuse is susceptible to some of the same criticisms that have been leveled at modular approaches. Specifically, neural reuse theories state that: (1) the “working” of a given brain circuit is fixed, rather than shaped by its input, and (2) that high-level cognitive behaviors can be cleanly mapped onto a specific set of brain circuits in a non-contextualized manner.

Chemistry, genetics, physics, and linguistics all present instances of reuse. I use the example of how behavioral constraints may have contributed to the emergence of phonemic reuse. Arising from specific facts about speech production, perception, and learning, such constraints suggest that combinatorial reuse is domain-specific. This implies that it would be more prudent to view instances of neural reuse not as reflecting a “fundamental organizational principle,” but as a fortuitous set of converging phenomena.

In this commentary we suggest that asymmetries in reasoning associated with moral judgment do not necessarily invalidate a theory-theory account of naïve psychological reasoning. The asymmetries may reflect a core knowledge assumption that human nature is prosocial, an assumption that heightens vigilance for antisocial dispositions, which in turn leads to differing assumptions about what is the presumed topic of conversation.

Neural reuse posits development of functional overlap in brain system circuits to accommodate complex evolutionary functions. Evolutionary adaptation evolved neural circuits that have been exploited for many uses. One such use is engaging cognitive processes in memory consolidation during the neurobiological states of sleep. Neural reuse, therefore, should not be limited to neural circuitry, but be extended to include sleep-state associated memory processes.

In criminal law, foresight betrays a guilty mind as much as intent does: both reveal that the agent is not properly motivated to avoid an illegal state of affairs. This commonality warrants our judgment that the state is brought about intentionally, even when unintended. In contrast to Knobe, I thus retain the idea that acting intentionally is acting with a certain frame of mind.

We propose Knobe's explanation of his cases encounters a dilemma: Either his explanation works and, counterintuitively, morality is not at the heart of these effects; or morality is at the heart of the effects and Knobe's explanation does not succeed. This dilemma is then used to temper the use of the Knobe paradigm for discovering moral norms.

Knobe relies on unhelpful analogies in stating his main thesis about the mind. It isn't clear what saying the mind works, or doesn't work, “like a modern university” or “a scientific investigation” means. We suggest he should say that some think that human cognition respects a ban on fallacies of relevance, where considerations actually irrelevant to truth are taken as evidence. His research shows that no such ban is respected.

Reuse is well established in molecular evolution; some analogies from this better understood field may help suggest specific aspects of reuse of neural circuits.

Children learn from people and about people simultaneously; that is, children consider evidentiary qualities of human actions which cross traditional domain boundaries. We propose that Knobe's moral asymmetries are a natural consequence of this learning process: the way “child scientists” gather evidence for causation, intention, and morality through early social experiences.