Full Idea
If the desire for wealth or health is desirable, we ought not to purse wealth or health, lest by acquiring them we cease to desire them any longer.
Gist of Idea
If a desire is itself desirable, then we shouldn't desire it, as achieving it destroys it
Source
Sextus Empiricus (Against the Ethicists (one book) [c.180], II.81)
Book Reference
Sextus Empiricus: 'Against the Physicists/Against the Ethicists', ed/tr. Bury,R.G. [Harvard Loeb 1997], p.425
A Reaction
He is investigating whether desires can be desirable, and if so which ones. Roots of this are in Plato's 'Gorgias' on drinking water. Similar to 'if compassion is the highest good then we need lots of suffering'. Desire must be a means, not an end.