Everyone is familiar with the story of Pavlov's dog. On day one, Pavlov went to the dog's cage, rang a bell, and gave the dog food – happy dog. On day two, Pavlov went to the cage again, rang the bell, and once more gave the dog food – very happy dog. On day three, Pavlov approached the cage, rang the bell, and this time, before he could even give the dog any food, the dog began to salivate. The dog had been conditioned to respond to the sound of the bell.
But an earlier experiment that few people know about is the one that Pavlov performed with his cat. The following is a transcript of Pavlov's notes.
Day 1: Went to cat's cage, rang bell, gave the cat food but it just rolled over and looked at me as if to ask what that awful noise was.
Day 2: Went to cat's cage, rang bell, gave the cat food and it yawned.
Day 3: Went to cat's cage, cat was nowhere to be seen, must have run off.
Day 7: Found cat in neighbour's garage under the hood of his car.
Day 8: Went to cat's cage, rang bell, but it was silent, looked to find that cat had stolen clapper.
Day 9: Woke up in the middle of the night to loud ringing, went to cat's cage, took bell away from cat.
Day 10: Went to pet store, bought dog.
Adapted from an Eddie Izzard skit.