Squid are pretty smart and intelligent.
It is believed that squids are slightly less intelligent than octopuses and cuttlefish; however, various species of squid are much more social and display greater social communications, etc, leading to some researchers concluding that squids are on par with dogs in terms of intelligence.
The coleoidea sub-class of the cephalopods includes the orders of cuttlefish, squid and octopuses and it is these (particularly the latter two) which are considered the most intelligent.
The modern cephalopods, a group including octopus, cuttlefish and squid, have famously complex brains, approaching that of a dog and surpassing mice and rats, at least in neuronal number.
Invertebrates, which are animals without backbones, are often considered simple and dumb, with no brains at all.
But the cousins of clams and oysters, the cephalopods (octopuses, squids, cuttlefish), have complex nervous systems and behaviors, as well as excellent vision.
A science-based report from the University of British Columbia to the Canadian Federal Government has been quoted as stating.
The cephalopods, including octopus and squid, have a remarkably well developed nervous system and may well be capable of experiencing pain and suffering.