In the remainder of his life, however, Nietzsche seems to have caught an early dose of syphilis, very probably during his first-ever sexual encounter, which gave him crushing migraine headaches and attacks of blindness and metastasized into dementia and paralysis. This, while it did not kill him right away, certainly contributed to his death and cannot possibly, in the meanwhile, be said to have made him stronger. In the course of his mental decline, he became convinced that the most important possible cultural feat would be to prove that the plays of Shakespeare had been written by Bacon. This is an unfailing sign of advanced intellectual and mental prostration.
via Christopher Hitchens Takes on Nietzsche: Am I Really Stronger? | Culture | Vanity Fair.