In this passage, Plato treats the pleasures of learning as restitutive, since they consist in one's ignorance being displaced by knowledge.
45) This implies that there is a state befitting beings who are perfect, and hence impervious to restitutive processes: happiness, or, as I shall refer to it, fulfillment.
50) Of course, insofar as we can never fully and stably achieve the divine state of fulfillment, we will never cease to undergo pleasant restitutive processes--there is always more knowledge and virtue to be gained.
Pleasure, I have argued, is to be identified with the restitutive processes by which we come to resemble god, fulfillment, with the state of completion and perfection that characterizes god.
While we might welcome restitutive pleasures for the sake of the state of repletion they offer, we could learn to value the state of repletion above all else, and wish that it might persist to the extent possible, even at the expense of the pleasures of restitution.
As I maintain in the conclusion of this paper, Plato is committed to the view that humans are, by nature, motivated by pleasure, and, further, cannot avoid undergoing pleasureful restitutive processes such as being heated and cooled; in that case, while he might allow that certain deviant or ignorant humans might choose the ahedonic life, they certainly could not live it.
However, the fifth class of the good includes the pure pleasure of learning, which Plato clearly states is restitutive, although it proceeds from an unfelt lack (51a7-2a3).
40b2-4); for Plato, these pleasures are the anticipations of restitutive pleasures (32b6-c2), and arise due to a current state of neediness (35e9-6b9).
I believe that this better reflects Plato's usage, since Plato only uses hedone to refer to restitutive pleasures, and that it captures the fact that the two states are importantly distinct: fulfillment is what pleasurable restitutive processes aim at.
51) Note that even if the best human life is largely made up of pleasant restitutive processes, insofar as we are rational, these are not themselves our telos: what we aim at is knowing, not learning.
Wieder/zero correspondencies involving English seem to be found predominantly in prototypical restitutive contexts where the presupposition triggered by the adverb is satisfied completely in the local context immediately to the left of the modified clause or VP; cf.
In (12), for instance, the restitutive adverb, modifying the metaphorical VP die Kriegsflagge zu hissen/to hoist the flag, cannot be omitted: it triggers the presupposition that the resultant state, that is, the flag being up, has obtained before or in other words, that the change of state described as 'to hoist the flag' reverses a preceding change of state ('to lower the flag').
Repetitive wieder/again tends to occur in a greater distance from its antecedent than the restitutive variety (Fabricius-Hansen 2001; Saebo 2004).
19) But as with redundant restitutive wieder, German native speakers would probably find the version without the connective less felicitous (cf.
Sections 7 and 8), there are two other uses of igjen, with the meaning of 'shut' and 'left (over)' (German ubrig), that are neither repetitive nor restitutive.