Foucault's analysis of ancient philosophical texts as well as the divergent interpretations that I have proposed in earlier chapters both make use of the distinction between the male and the female. But this distinction could refer to either biological sex or social gender. The relationship between the two, and a reference to biological sex differences, has long been the subject of heated controversy in feminist theory. This debate is not only of systematic interest, it also compels scholars who interpret ancient texts dealing with moral attitudes towards sexuality to reflect explicitly on the form of their historical reference to the male and the female.

The notion of gender would appear to be dependent on and relative to historical and cultural contexts and is therefore often assumed to be socially constructed. This means, however, that in historical studies, for instance on ancient culture, this notion cannot be applied without further qualification, in particular where such studies are intended to contribute to an understanding of historical attitudes towards sexuality, and thus more generally towards gender. Post-modern thought as influenced by Foucault has seen an increasing tendency to refer solely to the concept of social gender, and to brand any reference to biological sex as naive and patriarchal. Influential feminist approaches have interpreted Foucault in a manner that threatens to deprive his historical studies on sexuality of an important, if trivial, foundation – the reference to the sexes beyond cultural boundaries and specifications.

A crucial part of Foucault's ethics programme consists in looking at the forms of moral regulation which were involved in the behaviour of the husband towards his wife, and of the pederast towards his young beloved, in classical antiquity. Foucault has good reasons for thinking that the way in which the role of dominant partners in asymmetrical relationships is problematised should provide particularly revealing insights into moral attitudes to sexuality. According to Foucault, when moralists of the classical period prescribe sexual moderation for the husband or the pederast in spite of his dominant social position, then this is an act of disciplining which has little to do with respect for the interests of an equal partner in a relationship, i.e. with the adoption of a ‘moral position’ in the Kantian sense. Rather it is a question of demonstrating a self-control that gives one's life an aesthetic splendour and recommends one for a political career. ‘Govern yourself no less than your subjects and consider that you are in the highest sense a king when you are a slave to no pleasure, but rule over your desires more firmly than over your people’ is Isocrates' advice in a speech delivered to the young monarch Nicocles. Nicocles' own speech to his people (which Isocrates also wrote) is a detailed proof of his ‘self-mastery as a moral precondition for leading others’, as Foucault puts it: political leadership can and should be unhesitatingly entrusted to a monarch who can demonstrate that he is master of himself.

Foucault's analysis of Platonic erotics brings him to an extremely complicated domain of classical ancient philosophy, and one that can be discussed from a number of angles. In the ‘relation to truth’ he sees the decisive new perspective Plato introduces into the classical Greek theory on love.

Within this new framework of erotics Foucault correctly diagnoses a series of fundamental shifts in the problematisation of love in the relevant Platonic dialogues, in particular the transition

• from the question of behaviour in love, to the question of the nature of love;

• from the question of the honour of the boy, to the question of the love of truth;

• from the question of the asymmetry of erotic relationships, to the question of the convergence of mutual love;

• from the question of the virtue of the beloved, to the question of love for the master and his virtue.

Foucault begins his analysis of classical ancient philosophy by looking at the ethical discourses that deal with sexual pleasure and its problematisation. This he does on the same four levels that he had previously identified as the central aspects of every ethical investigation – ethical substance, the mode of subjugation, the teleology and ethical work (i.e. the practice of the self that the subjects must be engaged in to transform themselves into moral persons). The textual basis he employs consists almost exclusively of passages from the works of Plato, Aristotle and Xenophon. The main results of his analyses of these texts can be summarised as follows.

The crucial passages studied by Foucault identify the aphrodosia – the dynamic of the interconnection of desires, sexual activity and pleasure which threatens to exceed all confines and destroy all order and reason – as the central subject of moral concern, that is as the ethical substance. Two main parameters are at the heart of the analysis of this dynamic: the quantitative degree of activity and the sexual polarity. It is not the forms of love and its practices that are important for the moral problematisation of pleasure, but the number and frequency of sexual acts, as well as the differentiation between the subject and the object of appetite – that is matters of moderation and greed, and of activity and passivity, in both heterosexual and homoerotic relationships. Appetite and pleasure are considered to be natural and necessary, and so are not intrinsically bad.

According to Foucault, classical medical texts on the guidelines for an ideal regimen provide further instructive illustrations of the ways in which sexuality was problematised in the ancient world. One of the most important results of his analysis of these texts is that ancient dietetics develops a comprehensive perspective of bodily activity: it regulates nourishment, physical exercise, sleep, bathing and sometimes sexuality too. Foucault points to a number of important parameters that ancient dietetics relies on – the quantity, the overall state of the body, the length of time, the season, the general climate, general human nature; nor should the relationship of all these aspects to each other be forgotten. As Foucault sees it, ancient dietetics does not just suggest isolated rules for good health, but an overall regulation of life that covers both the mental and the moral aspect. Ancient dietetics pre-supposes not only that the care of the body and of the soul are mutually dependent on each other, it also maintains that mental discipline is a precondition of a successful regimen; above all, the primary aim of dietetics is not the unqualified prolongation of life, but the optimisation of the quality of life, that is the maximisation of pleasurable health within natural bounds. This goal depends on a concept of the good life, for following rational dietetic regulations is an indication of the mental self-control which is an intrinsic part of a good life.

According to one influential interpretation, in his later years Foucault turned his attention to the ‘practice of an intellectual freedom’ which ‘goes beyond the modern relationships between will, power and subjectivity’. This reading claims that Foucault's ethics aims to be – at least partly – free of the process of regulation and discipline which the analysis of power had revealed to be the all-pervasive element of the modern age, and maintains that it is concerned with ‘effective resistance to a wide-spread type of power’ and to modern ‘forms of dominance and exploitation’. It is in precisely this sense that Foucault's ethics is supposed to be political, while at the same time it is the last, perhaps even the most important, step in his attempt to subvert psychoanalytically based interpretations of the self, and to demonstrate that they are a form of coercion and political power to which psychoanalysis subjects our desire and our unconscious. Finally, the ethics as a practice of liberation is intended to provide an aesthetics of existence ‘which resists the science of life’ and ‘frees us from the empire of scientific knowledge’.

The general direction of this interpretation is quite clear. Foucault's opposition to universal anthropological, moral and rationalist categories has reaped criticism from influential authors such as Charles Taylor and Jürgen Habermas, who accuse him of abandoning all critical potential, with the result that he is unable to appreciate his historical analyses as an integral part of an emancipatory movement.

One feature the philosophies we have examined so far have in common is that for them the energeia of God has no specifically religious importance. It is philosophically important, of course, because the existence and character of the world are to be understood in light of it. Yet it plays no role in the religious quest to know God. The nearest to an exception is Aristotle, for whom we must strive to “make ourselves immortal so far as we can” by sharing in the divine activity of contemplation (Nic. Eth.x.7–8). Aristotle does not conceive of this as a way of coming into communion with God, however, but only as a way of achieving well-being by living in accordance with the best element in ourselves. He also does not make much use in this connection of the concept of energeia. Contemplation is also important for the Neoplatonists, but they too do not associate it with the divine energeia, and indeed for them the divine energeia in the highest sense is non-intellective.

We must look elsewhere for the role of energeia in religious thought. When we do, we find that it begins to play a minor but intriguing part in the first century a.d., one that grows as the centuries progress. By about the fourth century both pagans and Christians can be found understanding their religious life as a way of participating in the divine energeia.

We have now completed our historical survey. It would be possible to carry the story further, for the decades after the hesychast controversy saw a substantial interest in Aquinas among the Byzantines. The Summa Contra Gentiles was translated into Greek in 1355, and other works, including the Summa Theologiae, soon followed. They provoked a lively controversy, with a small but vigorous minority (led by the translators, Demetrius and Prochorus Cydones) seeking to persuade their countrymen of the merits of Thomism. This sudden expansion of horizons contributed to the turbulence of Byzantine intellectual life in its final days, helping make possible the originality of men like Gemisto Plethon and Cardinal Bessarion, who initiated the revival of Platonism in the Renaissance. No doubt it was the Byzantines' growing sense of desperation that opened their minds to the possibility that they might have something to learn from the West.

What has Athens to do with Jerusalem? That is a question that no student of western culture can avoid. Tertullian, who first posed it, did so in the course of accusing philosophy of engendering heresy. The implication behind his question was that Athens and Jerusalem are two different worlds, and therefore categories deriving from Greek thought should have no place within the Christian faith. Yet even Tertullian found it impossible in practice to maintain such a strict division. The Church as a whole tended instead to follow the lead of the Greek apologists, who had drawn freely on Greek philosophy in interpreting the Christian message. Ultimately the many forms of Christian thought that vied for pre-eminence throughout the Middle Ages and Renaissance, and into the early modern era, almost invariably owed much to both of Tertullian's opposing worlds. The result is that Athens and Jerusalem have been deeply and inextricably intertwined in the formation of western culture.

This fusion gives to Tertullian's question a different and more alarming meaning. Viewed in light of the intervening history, the question is not simply whether Christian theology should make use of Greek philosophy; it is whether the two great sources of our civilization are compatible. To hold that they are not is necessarily to put into question, not only at least one of them (and perhaps both), but also the civilization that grew out of their union.

The eastern tradition as we have presented it so far is rich but polyphonic. One finds terms as fundamental as energeia and “the things around God” being used differently by different authors, and concepts such as ceaseless prayer and the uncreated light achieving great importance without any attempt to incorporate them into a dogmatic synthesis. No doubt part of the reason was the strong sense of unanimity within the tradition as a whole. There was never any sudden loss of texts, or division into schools, or rise of a scholastic method – all factors that, had they occurred, would have encouraged authors to look for shortcomings within the tradition and to emphasize their own originality. The Byzantines took for granted that what had been said by the Fathers was correct and complete, and they saw their own task as that of applying this inherited wisdom to the issues at hand. Consequently, even a step of great originality was rarely heralded as such. Behind this conservatism there lay also a deeper cause, namely the apophaticism at the root of the entire tradition. What is the point of spinning out words about God when He can be known only through practice? On such a view theology, however complex it may become, is ultimately simply the enterprise of preserving “the faith once delivered to the saints.”

With Plotinus (c. 205–270) we are again in the presence of a philosophical mind of the first rank. Plotinus is conventionally regarded as the founder of Neoplatonism, and it is certainly true that he looks to Plato for inspiration more than to any other philosopher. But scholars have long recognized that in many ways he is as much indebted to Aristotle as to Plato. Something of Plotinus' attitude to Aristotle emerges in the following passage of the Life of Plotinus by Porphyry, who was Plotinus' student and an important philosopher in his own right.

As A. H. Armstrong remarks in a note on this passage, it “shows clearly how scholarly and professional a philosopher Plotinus was and how he worked, though with great originality, on the basis of an extensive school tradition.”

The history of Christian thought in the East after Dionysius is often presented as a series of controversies: the Christological controversies, the iconoclast controversy, the filioque controversy, the hesychast controversy. Although this approach works well for describing the growth of Christian doctrine, it is less suited to uncovering the philosophical presuppositions that shaped the eastern Christian worldview. The question of where philosophy ends and theology begins within the eastern context is not one that has an easy answer, nor do we need to settle it here. It is sufficient to note that there are recognizable philosophical issues on which the authors of this period have a great deal to say: issues such as the status and meaning of nature; the relationship between body and soul, and the sensible and the intelligible; the way in which symbols and images represent their prototypes; the interconnection of theory and practice; person as a category irreducible to nature; and, above all, the nature of God and the possibility of human communion with the divine. On such topics the thought of the Christian East is best approached, not in terms of doctrinal history, but as the gradual working out of the fundamental revision of Neoplatonism begun by the Cappadocians and Dionysius.

In this chapter our aim is not to present a comprehensive history of eastern Christian thought even in its philosophical dimension. The thread we are tracing is energeia.

Although Aristotle never takes credit for coining the word energeia, there can be little doubt that it was his own invention. It appears nowhere in extant Greek literature prior to Aristotle, and even for some decades after his death it is restricted mainly to philosophical writers, particularly those of Aristotle's own school. By contrast, it occurs 671 times in Aristotle's works, about once for every other page of the Berlin edition. Unfortunately Aristotle discusses its etymology only once, remarking briefly that energeia is derived from “deed” or “thing done” (τὸ ἔργον) (Met. ix.8 1050a22). Although this gives us the ultimate source of the term, the combination of en with ergon already had precedents in Greek, and it is likely that one of these was the more proximate source. The two available candidates are energos, an adjective meaning “active, effective,” and energein, a verb meaning “to be active or effective, to operate.” In either case the root sense of energeia is something like “activity, operation, or effectiveness.” To say more than this based on etymology would be rash.

One way to proceed at this point would be to list its various meanings in dictionary fashion, illustrating each by representative texts. Such a procedure would not explain what united the various meanings in Aristotle's mind and why he believed it appropriate to use the same term for them all. It would thus risk missing the term's more subtle nuances.

The story of the diffusion of Aristotelianism during the centuries after Aristotle's death is a long and tangled one. The works making up the Corpus Aristotelicum as we know it seem to have originated as notes written for lectures to students in the Lyceum. Aristotle also wrote a number of more popular works, the so-called “exoteric” writings which today survive only in fragments. Among these is the Protrepticus, whose treatment of energeia was discussed in Chapter 1. There is general agreement that the exoteric works were in circulation during the Hellenistic period, and that as late as the second century a.d. they still formed the main basis for the educated public's understanding of Aristotle. The fate of the school treatises is more obscure. According to a story told by Strabo and Plutarch, “Aristotle's books” passed at his death into the hands of Theophrastus, Aristotle's student and colleague, and the second head of the Lyceum. Theophrastus in turn bequeathed them to Neleus of Skepsis, who removed them to his hometown. There they languished in obscurity until they were recovered toward the end of the second century b.c. by Apellicon, a bibliophile who brought them to Athens. He published a faulty and apparently little noticed edition. Finally, about the middle of the first century b.c., a corrected edition was published by a professional Aristotelian scholar named Andronicus of Rhodes. All subsequent manuscripts of the school treatises ultimately rely on this Andronican edition.

After the death of Plotinus the mantle of leadership among Platonists passed to his former student, Porphyry (232–c. 305). It has long been recognized that Porphyry played a major role in the formation of Neoplatonism in the western half of the Empire. Augustine, for example, discusses his views at length in Book x of The City of God, and Boethius relies on him heavily in the interpretation of Aristotle's logic. One of Porphyry's most influential acts was to write a commentary on the Chaldaean Oracles, an obscure piece of religio-philosophical verse dating from the middle of the second century. By doing so he brought into the orbit of Neoplatonism the system of ritualized interaction with the gods known as theurgy. Porphyry himself had strong doubts about theurgy; he regarded it as at best a useful way of cleansing the soul, one merely preparatory for the only true salvation, which is achieved through philosophy. But his student Iamblichus rose to its defense, and this quarrel between Porphyry and Iamblichus marked a major parting of the ways in the early history of the school. Iamblichus' writings ultimately became definitive for Neoplatonism in the eastern half of the Empire, whereas they remained virtually unknown in the West.

In this chapter we will examine Porphyry and other Neoplatonists of the West. Part of our story will be that of how energeia as it is found in Plotinus and Porphyry was transformed into the medieval (and especially Thomistic) concept of esse, the “act of being.”