fundamental, independent of, and basic to, an explanation of the rest; and his views on this undergo
change. In the Categories, usually accepted as an early work, concrete individuals such as Socrates and
Coriscus fill this bill, and are called 'first substances'. In the Metaphysics, especially the difficult central
books, substance appears to be not the individual but its form, and difficulties arise which are not clearly
solved, given some of the other metaphysical roles that form plays. Aristotle's views here have been very
variously interpreted and estimated; and it is more obvious here than in other parts of his work that what
matters for him is getting properly to the roots of a difficulty rather than coming up with simple answers
to the problem as originally posed. On one point he never wavers: hostility to Plato's Forms (or numbers
or other abstract objects) conceived of as separate from the world we experience, existing independently
of it. It is crucial that we do have understanding of the world; a theory must be wrong that cuts us off
from what is supposed to make the world intelligible.
A most striking advance on his philosophical inheritance, and the only case where Aristotle consciously
claims to innovate, is his great clarification of the nature of argument. The Topics and Sophistical
Refutations are early records of his study of 'how to argue effectively'; but his real breakthrough is
marked by the Prior Analytics, the first work of formal logic, where by the use of schematic letters he
first isolates the notion of logical form and systematically classifies the forms of valid argument. Having
made it possible for the first time to distinguish the soundness of an argument from its power to
persuade Aristotle also, in the Rhetoric, performs the complementary task of classifying the various
sources of persuasion in argument. To sort out so rigorously and definitively the various aspects of the
'art of argument' from its muddled state in the fifth century, and even in Plato, was an amazing
achievement, displaying both the powers of Aristotle's intellect and his concern not to lose any aspect of
the subject he is analysing. The logical and rhetorical works remained more prominent in estimations of
Aristotle until the twentieth century; new developments in logic have shown the limitations of
Aristotelian logic rather strikingly, and rhetoric is no longer a serious study. As a result it is easy for us
to undervalue what appeared to Aristotle's contemporaries (and rightly to Aristotle himself) as an
unparalleled achievement.
Aristotle devotes a large proportion of his philosophical energy to the study of people in society and to
various phenomena of social life. Sometimes these are activities which Plato had attacked, such as
drama and the arts, and Aristotle's subtle and complex theory of various literary genres in the Poetics can
be seen as rescuing them from Plato's needlessly intemperate attacks. But mostly Aristotle carries on
from Plato fairly directly; one such area is that of the monumental studies of society in the late
dialogues. We have a number of works now grouped as the Politics, and three works on ethics; the
Nicomachean and Eudemian Ethics, and the Magna Moralia. (The relation of the first two is very
disputed, and so is the authenticity of the third.) Aristotle also deepens and carries further Plato's later
interest in history as casting light on present political arrangements: he organizes research into the
histories of the institutions of a large number of Greek states (one of these, the Constitution of Athens,
survives) and makes chronological improvements to the important public records of athletic victors. The
distribution of his interests reflects closely what we find in the physical works: thorough research is
vital, but it is guided always by a concern for theoretical clarity. (Historians' appreciation of his work has
thus varied a great deal, depending on how theoretical their own conception of their subject has been.)
Aristotle is not philosophically interested in history for its own sake, as we can see from a famous aside