Did you know that the ancient Egyptians associated cats with worship of the moon? The cat was sacred to the goddess Isis, who symbolized the moon. The cat too was believed to be a symbol of the moon, partly because cats are more active after dark, partly because the pupil of the cat’s eye reminded people of the waxing and waning of the moon. A cat’s pupils can change from the narrowest slits to the widest circles—exactly as the moon does.