Science is about having an organised route into a subject.
Only brains are known to do it. This closes off a lot of the more spooky possibilities. This means the mind has a history and a continuum that runs back from humans down through monkeys, cats, sea squirts and amoebas. A proper science of the mind would need to have the evolutionary perspective running through it like a seam. It would be the intellectual backbone of the field just as it is in biology.