Full Idea
I hope [psychologists] are actually brave, generous, proud animals, who know how to control their own pleasure and pain and are taught to sacrifice desirability to truth, even a bitter, ugly, unchristian, immoral truth - Because there are such truths.
Gist of Idea
Psychologists should be brave and proud, and prefer truth to desires, even when it is ugly
Source
Friedrich Nietzsche (On the Genealogy of Morals [1887], I.§01)
Book Reference
Nietzsche,Friedrich: 'On the Genealogy of Morals', ed/tr. Diethe, Carol [CUP 1997], p.11
A Reaction
A nice expression of Nietzsche's values, which makes truth central, contrary to the widespread modern view that he was the high priest of relativism. If you think that, read him more carefully.