> consciousness is a matter of degree

That's true, but that doesn't mean that thermostats are conscious. Shortness is "a matter of degree" too. Nonetheless, Danny Devito is short (4'10"), and Michael Jordan (6'6") is not. We can argue about Tom Cruise (5'7") and Johnny Depp (5'10"), and with regards to consciousness, we can argue about dolphins and dogs and maybe even cockroaches. But not plants and not thermostats.