If the the student has no topic of his own, he should not even think of a PhD.

“On this note, he quotes mathematician and family friend Jacques Hadamard, apparently complaining about a student who asked for a thesis topic, “Can you imagine that? If he has no topic of his own, he should not even think of a Ph.D.!””

Which brings to mind David Hubel’s practice of trying to persuade students not to do a PhD — he only wanted the ones who ‘really’  wanted it, rather than those who were just judged able.

From a book review of Fractalist in Science