Close to Tokyo’s Ueno Park, the Kan’ei-ji temple is a quiet pagoda far removed from the hustle and bustle of the park’s top tourists draw. The Buddhist temple is home to a remarkable monument: a simple engraved stone that is a memorial to the souls of dead insects. It was built to console the spirits of the flies, crickets, and grasshoppers that were killed during a 19th century anatomical study of insects.