Cephalopods are an island of mental complexity in the sea of invertebrate animals

Cephalopods are an island of mental complexity in the sea of invertebrate animals. Because our most recent common ancestor was so simple and lies so far back, cephalopods are an independent experiment in the evolution of large brains and complex behavior. If we can make contact with cephalopods as sentient beings, it is not because of a shared history, not because of kinship, but because evolution built minds twice over. This is probably the closest we will come to meeting an intelligent alien.

P. Godfrey-Smith, Other minds: the octopus and the evolution of intelligent life (2017), loc. 127