Of course fish are smart. Even the Romans knew that

Dr Culum Brown of Macquarie University, Australia, has been doing some research on fish, and concludes that they are intelligent, live in social communities (etc) and generally display ‘behavioural and cognitive sophistication’. Dr Brown’s research would seem to have consisted of reading the 2nd Century AD essayist Plutarch.

In a treatise on the cleverness of animals, Plutarch stages a debate between the pro-animal and pro-fish lobby. Aristotimus, for the animal lobby, states that all living creatures have many human qualities. They demonstrate capacity for purpose, planning for the future, memory, perception, emotion, care for their young, gratitude, courage, sociability, continence, self-control and bigheartedness. He proceeds to prove this with reference to animals.

Phaedimus, for the fish lobby, argues that, since fish have no contact with humans, they cannot learn their behaviour from them. It must be innate. Their superiority is shown in a number of ways. They deliberately make themselves extremely difficult to capture; the sea bass actually throws off the hook by swinging its mouth from side to side to widen the wound. If a parrotfish swallows a hook, others show collective solidity and nibble it away. Society-loving tunnies are geometers: they form themselves into a cubic shape to eat and school together. Companionship is shown by the crocodile, which makes friends with the plover, allowing it to clean his teeth, and by the pilot fish, which leads whales away from shallows.

Phaedimus saves the best for last: the dolphin, ‘the only creature that loves man for his own sake… a relationship sought by the best philosophers, a friendship for no advantage’. He tells the story of a close friendship between boy and a dolphin until one day, during a storm, the boy fell off the creature’s back and was drowned.