In the story "the devil and tom walker" what does tom do to make people think he is becoming crazy as he ages.

Some people think Tom Walker went a little crazy in his old age. After all, he did have his horse newly equipped and buried feet-up when it died, thinking that during the apocalypse the world would turn upside down and he’d need to ride at full speed to escape Old Scratch’s clutches

There flaw is their dicks