The paper submitted by ***** bears conclusive evidence of the profound and penetrating studies of the author in the area to which the topic dealt with belongs, of a diligent, genuinely mathematical spirit of research, and of a laudable and productive independence. The work is concise and, in part, even elegant: yet the majority of readers might well wish in some parts a still greater transparency of presentation. The whole is a worthy and valuable work, not only meeting the requisite standards which are commonly expected from doctoral dissertations, but surpassing them by far.
Sounds like a letter you’d read nowadays about a quite promising but perhaps not absolutely first-rate new Ph.D., right?
It’s what Gauss wrote about Riemann on the occasion of his thesis defense in 1851.
(Via this very interesting expose by Remmert.)
By the way, here’s what Gauss wrote for Dedekind’s thesis:
“The paper submitted by Mr. Dedekind [published in Dedekind’s Werke I, pp. 1-26] deals with problems in calculus which are by no means commonplace. The author not only shows very good knowledge in this field but also an independence which indicates favorable promise for his future achievements. As paper for admission to the examination this text is fully sufficient”.