The purpose of this thesis is to provide preliminaries for a better understanding of central
parts of Plato's philosophy. Its method is a combination of traditional diachronic semantics and
the study of the literary and social contexts of words which may be termed pragmatics. Its
justification, it is hoped, is provided by an application of the results of those studies to a portion
of Platonic text which is, in parts, reinterpreted in the light of some new findings.
The point of departure of the investigation undertaken is a passage from one of the dialogues
of Plato's middle period which is generally assumed to contain the essence of his thoughts on
matters ontological at the time of composition: Phaedo lOOd - 105e. From this text, a number
of significant terms, most of them recurring in other dialogues of similar date, have been
selected: fiSXSXSlV, 7tapstvai, 7tpOG£lV(Xl, fevetvai, sI8ck;, 'l5sa and some of their
cognates; the histories of these terms have been traced, from their earliest occurrence in extant
Greek literature, usually Homer, through the various authors and genres of epic, lyric and tragic
poetry, historical, philosophical, medical and rhetorical writings, to the early dialogues of Plato
himself. In the course of investigation it seemed appropriate to study the nouns 8t§OQ and
'l5ea in greater detail and to a degree approaching comprehensiveness, for two reasons: on the
one hand, their semantic development is more marked and variegated, and therefore deserved
more careful scrutiny; on the other, scholarly opinion, which has been taken into account
throughout, is more divided as to the meaning and senses of these two nouns than with any of
the other terms selected. For the same reason, it was deemed necessary to translate by far the
majority of pre-Platonic occurrences of the two nouns in their contexts - that often required
interpretation and discussion which may at first seem to be mere diversions - a measure not
required in the case of the verbs under consideration. That in itself is a first result: nouns are
more readily employed with extensions in meaning than verbs; they are more likely to acquire a
fixity in application which may amount to a technical terminology. The difference in status and
importance of the nouns over against the verbs is reflected in the separate arrangement of the
material in Parts I and II.
Part III consists of an application of some the results yielded by the semantic studies of the
individual words in Parts I and II. It is in the nature of the exercise that many of the J
developments traced in Parts I and II are not made use of in Part III; however, it was felt that
unless a complete study of all the various actual contexts prior in time were undertaken, it
would not be possible to determine with certainty the meaning and connotations of any given
term in any given text. The effort was not in vain, as it can be shown with fair precision not
only what the terms selected actually meant with Plato but more importantly, which literary
and intellectual contexts Plato derived his philosophical terminology from: being able to
determine to whom Plato reacted in his thoughts, and with whom he was in dialogue in his
writings, is more important than bare linguistic reconstruction of 'meaning'.
We see Plato in the central philosophical passage of the central dialogue Phaedo in interaction
with three at least partly distinct parties of pre-Socratic philosophers: Anaxagoras and his
followers, the Pythagoreans, and Democritus. While most of that conforms with received
opinion, reaction to Democritus at that early a stage in Plato's writing career is not usually
assumed. That in itself, and the use Plato makes of the thoughts of his predecessors in fusing
and correcting their assumptions while adapting their language to his own purposes may
prompt us to reconsider some commonly held views on Plato's ontology.
However, the study here attempted is intended to be preliminary in nature; the application to a
Platonic text in Part III is to be understood as one example only of how the semantic
investigations of Parts I and II may be applied to the dialogues of Plato and other near contemporary philosophical texts.