By 1912, Tesla began to withdraw from that doubting world. He was clearly showing signs of obsessive-compulsive disorder, and was potentially a high-functioning autistic. He became obsessed with cleanliness and fixated on the number three; he began shaking hands with people and washing his hands—all done in sets of three. He had to have 18 napkins on his table during meals, and would count his steps whenever he walked anywhere.
