The alternative interpretation is liberating in the sense that it can obviously explain all sort of pleasures, such as building, learning, eating when hungry, but also contemplating or just seeing something. But why, then, would Aristotle say that restorative processes are only incidentally pleasant? Restorative processes are activities, so why would they not be pleasures in their own right, but only incidentally? The answer emerges by considering, carefully, what it is that is only incidentally pleasant. I will do so by focusing on three cases of healing.
Case 1: A doctor cures an ill person.
The ill person is in a deficient condition: he is deprived of health. The point of the cure is to restore the ill person’s health. On this simple model it is entirely through the agency of the doctor that the ill person’s health is being restored; the patient is merely passive. The doctor is successful if he succeeds in imposing the form of health on the patient.31
This simplified model highlights two points. First, the doctor must have the form of health. But this does not mean that the doctor must be healthy himself (save that he must be sufficiently healthy to function as a doctor). Rather, the doctor has the form of health qua doctor: a doctor must have mastered the art of medicine, and this
entails that he knows what health is.32 This knowledge enables him
to impose the form of health on his patients.
Second, there is a clear difference between the doctor as the source of change and the patient as the subject of change. There is clearly a change in the patient, the subject of change: the patient changes from being potentially healthy to being actually healthy. A sign that the patient is the subject of a change (i.e. that it is predicated of him) is that after the doctor has cured the patient, there is nothing the doctor qua doctor can do for the patient - unless the patient falls ill again, i.e. changes back to being potentially (but not actually) healthy. Since the doctor cannot heal this healthy person - does this mean that there is also a change in the doctor? To see why Aristotle would answer negatively, it is useful to distinguish between ‘change belonging to X’ and ‘change in X’.33 There is a change that belongs to the doctor, since
he is the originator of this change. But it is crucial for Aristotle that this does not entail that there is also a change in the doctor.34 To this
effect, Aristotle argues in Phys. III.3 that agency can take place in a suitable medium distinct from the source of the change. Thus, to explain that the activity of healing belongs to the doctor, we need only one change: the change occurring in the patient. It is in virtue of the change in the patient that the successful doctor can no longer
32 In Met. 12.3.1070a28-30 medical art is said to be the form (logos) of health.
33 Aristotle makes this distinction in Phys. III.3.202b5-8. U. Coope 2004:205 captures this distinction as distinction between ‘change of’ vs ‘change in’, whereas A. Marmodoro 2007:210-11 speaks of it as distinction between ‘change belonging to’ vs ‘change occurring in’.
34 To be absolutely correct, this claim needs to be qualified in two ways: (1) given Aristotle’s account of causation, there is also a change in the agent when the agent’s acting involves touch, see Phys. III.2.202a3-7. This, however, is an additional process of change and can be left aside for present purposes. (2) There is, of course, a difference in the doctor: at one point he does not use his medical knowledge, at another he does. But Aristotle has reservations about calling this ‘change’, cf. DA II.4.416b2-4 and II.5.417b5-9 with Kosman 1969:55. See also EN X. 4.1174b12.
heal the patient; there is no extra change in the doctor. So, one could say that there is only one activity, the process of restoring health, but that the doctor and the patient stand in different relations towards it. The doctor is related to this activity as agent, whereas the ill person is related to it as patient. I shall refer to the agent’s relation to this activity as ‘agent-activity’.35
Case 2: A doctor is ill and cures himself.
That the doctor and the ill person are identical should make no difference to what holds true in the Case 1: agent and patient just happen to be the same person, and can be separated, logically, by the qua-locution. So, in this case, when the person heals himself, he is active qua doctor. Note that it is only qua patient that the person is in a deficient state, but not qua doctor: being curable essentially relies on privation of a certain state; being able to cure does not rely on privation.
Case 3: A person becomes healthy without a doctor.
The model of healing in this case also underlies the other two cases, if they are not simplified. For usually the doctor’s job is to stimulate the patient’s organism to heal itself (e.g. by inducing a fever). If there is no doctor - what is the source of the change in the patient? The only thing that could fill the bill is the agent-activity of the residual
natural state, mentioned in both T2 and T3.36
35 In describing causation as different relations to one activity, I remain neutral between the interpretation of causation as one event with two description (Waterlow 1982:180-82) and as ‘one-in-two entity’ (Marmodoro 2007:228)
36 D. Frede thinks that it is problematic to assign the process of restoration and the activity of the healthy part to different parts because there would be no connection between them (2009:195). On my interpretation, there is a causal connection: the residual healthy part heals the unhealthy part.