Explicates the continuum of pre-Socratic, Socratic and Platonic, and Aristotelian philosophy, from the first systematic inquiries into nature and man’s nature until the end of Hellenistic period, generally presenting matters on their own terms rather than in context of future history of philosophy.

Pre-Socratic: The theme of constant, dynamic opposition against underlying unity preoccupied the departure from mythology and religion. Pythagoras preceded Plato’s forms (and also Descartes’ cogito) with a dualist theory of soul and also the representational power of numbers. Parmenides debuted the precedence of reason (rationalism) over empirical evident, and the role of being (ontology) in argument and consequence. But the problem of non-being was unresolved. Democritus considered that science banished the common-sense experience of the world (whereas moderns consider science more an extension or an enhancement). Anaxagoras embodied the pre-Socratics’ system-building efforts, whereas post-Aristotelians (Skeptics, Stoics, Cynics, Epicureans) were essentially ethicists, seeking to live an untroubled life. Empedocles married religious trappings to a rational cosmology. Medicine and philosophy were closely related in the Greek world, as in the Hippocratic oath.

The Sophists, embodied by Protagoras, were not dispassionately seeking truth, contra Gottlieb, but foreshadowed relativism in their pursuit of ‘making the weaker argument the stronger’ or in ‘man is the measure of all things’. Sophism assimilates virtue to what is advantageous, pace Thrasymachus, since morality is no more than social convention. Gorgias doubted the reality of being itself, the better to operate at the level of seeming than to pursue knowledge.
Socrates invented the view of philosophy as a pursuit of how men should live, versus the pursuit of metaphysics. Epistemology and ethics, though distinctly separate in modern philosophy, cannot be so if virtue is knowledge. In Meno, the Platonic Socrates asks not for a list of virtues but what they have in common. New theories are to be subjected to the test of consistency with itself (i.e., if nothing is true, is that itself true?)

Plato, considering the soul immortal, thereby explains how it knows of immortal forms (i.e., the so-called theory of recollection). Forms are standards of judgment, guideposts in human knowledge. ‘Good’ is the super-form; thereafter come being, change, rest, sameness, difference. Being is pervaded by difference, thereby disposing of the problem of being arising from not being; for what is not is false, not nothing. To be explanatory, the cause must give rise of the outcome; the true cause should not be consistent with other effects (i.e., largeness does not produce smallness). Knowledge is always true whereas belief can be true or false, and ignorance is always false. More elaborately: imagination < belief < thought < understanding < knowledge. Dialectic is the process of hypothesizing and then discovering the principles which support the hypothesis. The dialectician divides the inquiry’s evidence along ‘natural joints’ of categorization. Language is built on a presumption of stability, of shared meaning (convention), even if usage changes just as substance changes. It is a likelihood not a permanence. Phaedo and Republic utilize unchanging forms and changing things that participate in them. Timaeus introduces the demiurge, the mover. Aristotle saw dialectic more simply as argument from agreed premises. Logic is categorical: statements relate subject to predicate, in order to proceed to the syllogism. A demonstrative syllogism shows not only that something is (or is not) the case but why. The premises of demonstrative syllogisms must identify essential features of the things in consideration. ‘Accidental’ features (a giraffe with a broken toe) are not significant, contra modern science. For Aristotle, epistemology is fairly the same as the philosophy of science (systematic exploration), save that episteme encompasses all disciplines. Also in contrast to modern empiricism (e.g., Hume): though sense experience stops the regress of endless demonstration, rational or even plausible deduction is permissible even though they may be overturned. Items in the world are primary, not derivative of forms: without beautiful things there's no such thing as beauty. Changes involves the nature or property, called form, and the underlying substance, matter. The four causes are the material (substance), the formal (definition or determination), the efficient (the dynamic) and the final (purpose). Substance has potential to actually become something else. As to ethics, one seeks not only the ideal life but the good life that earns the admiration of others. Virtue is achieved by those raised well – by habituation. The virtuous action lies between the extremes, the rational discernment or perception of right action in the circumstance; but there is the problem of ‘moral luck’, ethics as a product of happenstance, as a luxury. Only the virtuous can have friends, who share interests and right action. Sensation isn’t the same as imagination, which is closer to preliminary thinking; yet it is short of belief. Adamson’s treatment of Aristotle’s political philosophy is shallow.