The dialogues that have these characteristics, and are traditionally accepted as early, are: Apology (a
monologue), Crito, Euthyphro, Ion, Lesser Hippias, Greater Hippias, Laches, Lysis, Menexenus,
Protagoras, Euthydemus, Charmides, Lovers, Hipparchus, First Alcibiades. (The last three have been
excluded from the Platonic 'canon' since the nineteenth century, but for no good reason; so have a
number of others whose authenticity is more doubtful.)
Usually grouped as 'middle' dialogues are Gorgias, Meno, Phaedo, Symposium, Republic, Phaedrus,
Cratylus. With these some would put Timaeus with Critias; others would place these with the dialogues
usually grouped as 'late': Theaetetus, Parmenides, Sophist, Statesman, Philebus, Laws. The dialogues are
often 'placed' chronologically by the prominence of certain stylistic features, such as the avoidance of
hiatus; but this is a very fragile aid in the case of a conscious literary artist who revised his works. In any
case we do not yet possess an adequate statistical analysis of Plato's style. But a rough grouping of the
dialogues forces itself on us: the middle and late dialogues are radically different from the early ones.
They are much longer, mostly undramatic, especially in their use of Socrates, and above all are didactic.
The stylistic changes reflect a shift away from the personal urgency of Socratic enquiry: from the middle
dialogues on, we are in no doubt that Plato does have views of his own which the figure of Socrates
serves merely to present. When he gives us a theory of society (in the Republic) or a cosmology (in the
Timaeus) or a long set of arguments about the Eleatic One (in the Parmenides) the dialogue form is
serving merely to make the argument more accessible. Often it does not succeed in this; and sometimes
it produces an unsuitably casual drift in the argument or exposition. The dialogue form, and the use of
Socrates, become strained to breaking-point as Plato becomes ever more engaged in straightforward
philosophical debate, often with contemporary positions. All the same, Plato never wholly abandoned
dialogue, and clearly continued to value its detachment, and the avoidance it necessitates of more than a
mild degree of technicality and systematization of different positions.
His followers and interpreters (with a few exceptions such as the sceptical New Academy) have mostly
displayed a different spirit. The dialogue form has usually been taken as a way of communicating
different parts of a single system of ideas, a purely literary device which philosophers can safely ignore.
Such an approach is unsubtle and risks insensitivity to differences between different dialogues each of
which is self-contained. We can readily find in Plato continuing preoccupation with certain themes; but
to build a system of Platonic doctrines is to do what he never did. He never commits himself in propria
persona to any of the doctrines commonly thought of as Platonic; still less does he tell us which of the
ideas he discusses are most basic for him and what their relationships are. There are dangers also in
trying to go behind the elusive dialogue form to a supposedly more solid historical development of
Plato's thought and personality. The 'biographical' tradition is untrustworthy, going back to later
interpretations of the dialogues. There are several 'Letters' purporting to be by Plato, of which the
Seventh is often claimed as genuine. But forgery of 'letters' was quite standard with famous figures; the
'Seventh Letter' is so peculiar philosophically that it would be perverse to use it as a basis for
interpreting the philosophy in the dialogues; and it is as a whole such an unconvincing production that
its acceptance by many scholars is best seen as indicating the strength of their desire to find, behind the
detachment of the dialogues, something, no matter what, to which Plato is straightforwardly committed.
Plato himself thought it important to frustrate just this desire.