On October 1, 1861, Charles Darwin sat down to write a letter to his friend, the geologist Charles Lyell. It wasn’t his finest mood. “I am very poorly today & very stupid & hate everybody & everything,” he confessed. He went on to grumble that he lived “only to make blunders.” He also declared that he hated orchids, even though he was just beginning a book about them. 

Far from the cool detachment we often imagine of great scientists, Darwin’s note shows that even the most brilliant minds have off days. Click here to explore more eccentric routines, like Victor Hugo’s unusual method of staying productive when he was behind on his writing.