The psychology of Plato extends no further than the division of the
soul into the rational, irascible, and concupiscent elements, which, as
far as we know, was first made by him, and has been retained by
Aristotle and succeeding ethical writers. The chief difficulty in this
early analysis of the mind is to define exactly the place of the
irascible faculty (Greek), which may be variously described under the
terms righteous indignation, spirit, passion. It is the foundation of
courage, which includes in Plato moral courage, the courage of enduring
pain, and of surmounting intellectual difficulties, as well as of
meeting dangers in war. Though irrational, it inclines to side with the
rational: it cannot be aroused by punishment when justly inflicted: it
sometimes takes the form of an enthusiasm which sustains a man in the
performance of great actions. It is the ‘lion heart’ with which the
reason makes a treaty. On the other hand it is negative rather than
positive; it is indignant at wrong or falsehood, but does not, like
Love in the Symposium and Phaedrus, aspire to the vision of Truth or
Good. It is the peremptory military spirit which prevails in the
government of honour. It differs from anger (Greek), this latter term
having no accessory notion of righteous indignation. Although Aristotle
has retained the word, yet we may observe that ‘passion’ (Greek) has
with him lost its affinity to the rational and has become
indistinguishable from ‘anger’ (Greek). And to this vernacular use
Plato himself in the Laws seems to revert, though not always. By modern
philosophy too, as well as in our ordinary conversation, the words
anger or passion are employed almost exclusively in a bad sense; there
is no connotation of a just or reasonable cause by which they are
aroused. The feeling of ‘righteous indignation’ is too partial and
accidental to admit of our regarding it as a separate virtue or habit.
We are tempted also to doubt whether Plato is right in supposing that
an offender, however justly condemned, could be expected to acknowledge
the justice of his sentence; this is the spirit of a philosopher or
martyr rather than of a criminal.
We may observe how nearly Plato approaches Aristotle’s famous thesis,
that ‘good actions produce good habits.’ The words ‘as healthy
practices (Greek) produce health, so do just practices produce
justice,’ have a sound very like the Nicomachean Ethics. But we note
also that an incidental remark in Plato has become a far-reaching
principle in Aristotle, and an inseparable part of a great Ethical
system.