I was on holiday on Skyros, a Greek island and had been to a talk about a mile away. On the stroll back, among a group of about 30 people, I was telling my friend that I felt sad and lonely. It was a full moon and the white buildings were lit with moonlight. A black tom cat came out into the street, made straight for me and wriggled and purred in front of me, and no-one else, for a long way. My friend, a hard-boiled scientist, said she wouldn't have believed it if she hadn't seen it.