is fully displayed. Now knowledge is acquired only after years of preliminary training in mathematical
disciplines (inculcating the need to rely on argument rather than experience) and in 'dialectic' or
philosophical reasoning, in which 'hypotheses' about the nature of reality are put forward and
exhaustively tested by questioning until they can be fully and explicitly defended. Knowledge is
systematic and hierarchical: one's beliefs are understood only when one comes to see where they belong
in a system of truths where some are basic and some derived. Knowledge so conceived has two further
features: it can be imparted, and it requires time and effort, being achieved only by those who have
actually come to understand in context what others appreciate only in unintegrated fragments.
Unsurprisingly, knowledge will be something only few can attain, and most people's beliefs, however
individually well qualified, will not count. It does not follow from such a view that we cannot have
systematic understanding of the physical world we experience, but (with a few lapses) Plato's stress on
pure reasoning leaves no room for this.
The more emphasis is put on knowledge as grasp of an objective, shared, impartible system of
hierarchically ordered truths, the more we wonder what has happened to Plato's original concern to wake
each of us up to personal understanding as the basis of our actions. In the Republic Plato still insists on
the importance of the individual's own insight, and also insists that knowledge culminates in and flows
from the Good, and thus has practical import; but most readers are rightly not satisfied that Plato has
retained good grounds for this insistence. The original problems about knowledge that come alive in the
context of Socratic refutation have got lost.
In the later dialogues we find that, although Plato continues to assert that knowledge requires a rational
basis, he seems to have lost confidence in the middle-dialogues model. It is never explicitly argued
against or replaced, but it is not put to any use either, and Plato's last thoughts on knowledge are
inconclusive ones-the brilliant dialogue Theaetetus, where instead of giving us a model for knowledge
Plato turns at last to asking what knowledge actually is, and finds the answers, as many have since,
persistently elusive.
But the Republic model remains pervasive in interpretations of Plato, partly because it is impressive,
though vague and never given precise application, partly because it goes naturally with a similarly
impressive though vague conception of the reality that corresponds to knowledge.
The knowledge that interlocutors in the early dialogues lack is a grasp of the basis of whatever virtue is
in question. They cannot 'give an account' of it which will define the real nature which underlies its
various manifestations, and which explains and corrects our ordinary beliefs. What marks off the person
with understanding is grasp of what there is real and objective to know about bravery or beauty or
justice, or whatever is in dispute. This is what Plato calls (untechnically and with a variety of
vocabulary) the Form, the real basis of qualities like the virtues, which can be grasped only by people
who have thought and reasoned and is not accessible to those who wrangle blindly about their
experience without reflecting on it. Corresponding to the way that knowledge comes to be seen more
and more as systematized pure reasoning, the Forms come to be conceived of as objects of pure
thinking, cut off in a mysterious way from our experience.