Five, parrots have been
tested on this. They can describe abstract qualities of objects (color, shape, number, etc) correctly without a human telling them which is which. They know what they're talking about. They are said to have the intellectual capacity of the average 5ish-year-old human child.
Another parrot story:
The same parrot swooped me, and swooped the cat, both of whom he didn't like at the time. So his owner said offhandedly "Why don't you go and sweep the vacuum cleaner too if you're swooping everyone you don't like?" He is terribly afraid of vacuum cleaners. But he tried to swoop the vacuum cleaner, got a little closer than he liked, flew rapidly back to his cage, landed, and started laughing. (Yes, he laughs appropriately too. And cries when he is upset or wants to get sympathy, and it can be hard to tell the difference between those two with him because he's astute at manipulation.)
He asks for objects by name. If you don't understand what he's saying, he'll go for the object. You can ask him "Do you want ______?" If he says something it means "No." If he remains silent, it means "Yes." (And he will not cooperate with you if you try to take him towards the thing he doesn't want, he squawks up a storm. If you wait until he stays silent, though, he'll cooperate fully.)
He runs towards me and yells "Goodbye!" (or "bad lady dammit goodbye" if he's feeling loquacious) when he wants me to go home. (And yes he cusses quite appropriately too. He never yelled "Cat! ***!" unless he was flying at the cat, and for that matter he never said "cat" at all unless he was flying at the cat or standing above the cat on a bar and taunting her. Which drove her nuts.)
He's very clear on what he does and doesn't want, and if you do something totally different than he's asking for,
he'll let you know about it in no uncertain terms. He has to understand what he's saying because if he didn't, then his pissed-off reactions to doing things other than what he's asking for would not follow any particular pattern. They do. (This is a problem when he asks for things like mildew, which he considers a delicacy and of course nobody will let him have it.)
Here's a true story about one of the parrots they were doing research on:
Thus we are trying to get him to sound out refrigerator letters, the same way one would train children on phonics. We were doing demos at the Media Lab for our corporate sponsors; we had a very small amount of time scheduled and the visitors wanted to see Alex work. So we put a number of differently colored letters on the tray that we use, put the tray in front of Alex, and asked, "Alex, what sound is blue?" He answers, "Ssss." It was an "s", so we say "Good birdie" and he replies, "Want a nut."
Well, I don't want him sitting there using our limited amount of time to eat a nut, so I tell him to wait, and I ask, "What sound is green?" Alex answers, "Ssshh." He's right, it's "sh," and we go through the routine again: "Good parrot." "Want a nut." "Alex, wait. What sound is orange?" "ch." "Good bird!" "Want a nut." We're going on and on and Alex is clearly getting more and more frustrated. He finally gets very slitty-eyed and he looks at me and states, "Want a nut. Nnn, uh, tuh."
Not only could you imagine him thinking, "Hey, stupid, do I have to spell it for you?" but the point was that he had leaped over where we were and had begun sounding out the letters of the words for us. This was in a sense his way of saying to us, "I know where you're headed! Let's get on with it," which gave us the feeling that we were on the right track with what we were doing. These kinds of things don't happen in the lab on a daily basis, but when they do, they make you realize there's a lot more going on inside these little walnut-sized brains than you might at first imagine.
(From That Damn Bird)
Additionally, nobody is fully aware and a master of himself, totally free and responsible for what he does and doesn't do, anyone who believes that is deluding themselves (which humans are very good at doing). A ton of the work of the brain goes on outside of the conscious level, and I'm not just talking basic biological functions here. People who think they are in full control of themselves have another think coming eventually. That doesn't mean self-control shouldn't be striven for, but it's not ever going to be a total reality. And if you think animals don't have to learn self-control then you haven't observed them closely enough.