We shouldn't feel bad for a goldfish in a small bowl because the goldfish has a memory that is so short it will forget its surroundings by the time it reaches the other side of the bowl, right? Unfortunately this is a misconception that started somewhere and got passed down to the point that most people think it's true.
Scientific studies show that the memory of a goldfish last much longer than mere seconds. In fact, goldfish have the ability to retain memories for several months!
Three Second Memory Myth
Goldfish Do Not Have a 3 Second Memory
Granted, the memory span of a goldfish may exceed that of other types of fish and is certainly much less than that of a human, but it is not the few seconds that is commonly thought. So if you have a goldfish, maybe get your fish a bigger bowl.