I'm not even sure what you mean by it. And having a perception is not an essential property of anything. Being capable of thought certainly is a capacity. And it is a causal power if thought can affect the world. No, a change of words doesn't make for a change of reality.
Cats are such that if they can no longer breath, they die.
Assuming it isn't physically possible for a given cat to somehow acquire the ability to live without breathing, the ability to breath is an essential property of that cat. You can't do this with the identity criteria which I have given for minds. Neither can you do it with thoughts, feelings or willings. I was thinking of the objects of the intentional states, not the subject, tho it is certainly true that the particular organism is part of the identity of that intentional occurrence. It is the boundaries between objects which are decided by us.