The chapter considers why Plato thinks that Forms are unitary and changeless. It argues that this follows from Plato's supposition that Forms are essences and that the definition of essences must conform to certain requirements.

The chapter considers why Plato thinks that Forms are distinct from sense-perceptible things. It focuses on Phaedo 74 and Republic 478-480. It argues against the standard view that, for Plato, sense-perceptible things are subject to co-presence of opposites. Plato's view is rather that sense-perceptible things, in so far as they are simply perceived by the senses, are subject to co-presence of opposites.

The chapter is dedicated to the Sun Analogy in Republic. It shows that, for Plato, mind and world are co-ordinate: neither is prior to the other; and this is because both mind and world are co-explained by a single ultimate principle, which is super-ordinate to both mind and world: the Idea of the Good.

The chapter considers why, in Republic VII. 523-525, Plato associates Forms with judgements about sense-perceptible things. It argues that he does so because he argues that judgements about sense-peceptible things, if they are to conform to the principle of non-contradiction, must use certain Forms, and especially the Form of oneness or unity, to individuate sense-perceptible things.

The chapter considers Plato's claim, in Parmenides 135, that thinking about things requires Forms. It locates Plato's argument for this claim in 132 and, especially, in the second part of the dialogue (142ff.). It shows that the second part of the dialogue is just as much about thinking as it is about being.

This is the Conclusion, and it shows that that upshot of this project is that Forms simply are essences, not things that have an essence.

The chapter argues that Plato, in the Hippias Major gives due consideration to the question whether, for some qualities F, such as beauty, it is possible to give an account of what F is by pointing to an example-and-exemplar. He takes seriously, and gives cogent reasons in defense of, an affirmative answer to this question in a manner comparable to Geach – although he argues that these reasons lead to inconsistency, if combined with the view that it is possible to make comparisons in regard to F among significantly different examples-and-exemplars of a thing that is F.

The significance of this project ought to be evident. First, it shows that Plato’s Forms simply are essences, not things that have an essence and that Plato’s theory of Forms is just that, a theory of essence. Secondly, it shows that, if we have reason to raise and take seriously the ti esti (‘What is it?’) question, then we have reason to take seriously Plato’s theory of essence, the theory of Forms, with the remarkable characteristics that Plato attributes to essences and Forms. thirdly, it presents a challenge to those philosophers today who think that essentialism is an optional item on the philosophical menu. Finally, it presents a challenge to the tendency, typical to the essentialists of today, to think that the only option is Aristotelian essentialism, and that Platonic essentialism, if it can be made out at all, is simply Aristotelian essentialism with the addition of certain Platonic commitments that are both unattractive and optional. The projects demonstrate that Plato’s essentialism is a well-argued, rigorous and coherent theory, and a viable competitor to Aristotle’s essentialism.

The chapter considers why Plato thinks that Forms cannot be perceived by the senses. It argues that this is because Forms, or essences, cannot be defined by example and exemplar. It shows that this does not mean that Forms/essences can be known only a priori.

Given Socratic motivational intellectualism, self-improvement in the ethical domain requires self-improvement in the epistemic domain. Gives the details of Socratic epistemology and indicates the ways in which Socrates supposes we can improve our cognitive conditions. Explains the different sources of ignorance and how these can be controlled. Shows how some etiologies of belief-formation are more reliable than others, and how Socrates thinks we can learn to rely more on the more reliable ones and less on those that are less reliable. Explains how the Socratic “search for definitions” and elenctic refutations are exercises in cognitive self-improvement, which does not simply produce repeated failures, but instead greater comprehension of ethical concepts – even if such comprehension is never complete or perfect for a human being.

Explores Plato's hagiography of Socrates as one who is both an exemplary human being and imperfect in knowledge, virtue, and happiness. The way in which Socrates is an exemplar is not by achieving a standard of perfection, but by living a life dedicated to self-improvement in the most important things. Socrates sincerely acknowledges his own ignorance, but engages in dedicated inquiry in such a way as to mitigate that ignorance. By improving his cognitive condition, Socrates also improves his ethical condition. He becomes more virtuous and happier by both avoiding those errors that are avoidable and practicing the activities that can improve one’s life.

Does Socrates believe that virtue is necessary for happiness? If so, those who lack virtue cannot be happy. But virtue, Socrates also believes, is a kind of knowledge. Yet Socrates himself persistently disclaims having the kind of knowledge that seems to be required. If Plato’s exemplar of a human being lacked knowledge, he must therefore also have lacked virtue. Accordingly, some scholars have concluded that neither Socrates nor any other human being can have any positive happiness – just relative degrees of wretchedness – in life. Provides a much more optimistic account of the Socratic view in which the craft model allows for self-improvement in knowledge and virtue, to such a degree that some positive happiness is possible for even very imperfect human beings. Undertakes detailed analyses of important texts in which Socrates attributes some achievement in craftsmanship and argues that positive achievement does not entail a perfection standard or anything like mastery of a craft – including the most important craft of virtue.

Scholars have debated the various texts in which Socrates seems to indicate an extremely close – perhaps even logical or analytic – connection between virtue and happiness. Is virtue simply identical to happiness? Is virtue all that is needed – is it sufficient – for happiness? Some texts seem to indicate such a logical connection, but attributing the sufficiency thesis to Socrates also commits him to the view that even the worst disasters cannot make a good person unhappy or spoil a virtuous agent’s life. Other texts, however, seem to show that Socrates clearly did recognize our vulnerability to conditions that are beyond human control. Provides an interpretation of the Socratic view on this issue that denies the sufficiency thesis while maintaining a strong nomological connection between virtue and happiness. Greater virtue will always improve a human life, even if such improvement falls short of achieving positive happiness. Success comes in degrees, even in the most important pursuits.