In this letter dated 1 December 1869, Lotze begs Carl Stumpf not to become a priest but to return to science. Brentano also spoke to him in the same manner. Brentano's advance in particular is astonishing, since he himself was still a priest at that time.

The original letter is in the Adolf Würth Centre at the University of Würzburg.

"I cannot therefore accept your decision to become a priest in any other way than with all respect for your conscientious conviction, and although a fond hope thereby fails me, I nevertheless recognize too well the whole extent of the blessing which your spiritual power can bestow in this office to want to make a firmly made decision on your part difficult with any opposition. Nevertheless, forgive me, who loves you dearly, the one, somewhat serious request: do not take the decisive decision, the irrevocable one, too quickly in the early youth that you are still so fortunate to enjoy! Everything else I leave to your own expertise and consideration; but here I beg!"