Aristotle is here comparing σοφία with ὐγίεια and φρόνησις with ἰατρική.
ὐγίεια — σοφία
ἰατρική — φρόνησις
In order to understand the ground of this comparison, we need to consider the example of a man who is a doctor. If a doctor who is sick heals himself on the basis of the knowledge he has as a doctor, then that is a peculiar way to take care of his own Dasein by himself, to make his own Dasein healthy once again. A higher way of being healthy, however, is health itself. The healthy man does not at all need to be skilled in medicine in order to be healthy. He is healthy without further ado, i.e., he is simply what he is. Health is itself a mode of Being which keeps a man in the proper state of his bodily Being. Now the same applies to φρόνησις and σοφία. Φρόνησις leads and guides all human acting, but it is still dependent on something else, namely the action itself. But the θεωρεῖν of σοφία, on the contrary, does not, as is the case with ἰατρική, have a further goal; instead, it is carried out purely as such by the man who lives in it. Θεωρεῖν is a mode of Being in which man attains his highest mode of Being, his proper spiritual health.
There still remains a lacuna, however, in the understanding of the priority of σοφία, although we already understand that σοφία in a certain sense accomplishes something immediately, simply by the fact that it is there, whereas φρόνησις accomplishes something with regard to something other than itself. This structure is clear. Nevertheless, we cannot yet understand to what extent σοφία can be compared to human health, i.e., to what extent the comportment which is nothing but the disclosure of the everlasting constitutes the proper Being of man. We can come to understand it only on the basis of the meaning of the Greek concept of Being. Because precisely that to which σοφία is related is everlasting, and because σοφία is the purest way of comportment to, and of tarrying with, the everlasting, therefore σοφία, as a genuine positionality toward this highest mode of Being, is the highest possibility. The decision on the priority of σοφία is therefore made ultimately on the basis of that to which it relates. Ἐπιστήμη is excluded here since it cannot disclose the ἀρχαί but instead presupposes them. The constant tarrying with what is everlasting is the accomplishment of pure νοεῖν, which Aristotle also compares to αἴσθησις.3 In this manner we gain
3. Cf. p. 110ff.