I might not be heartbroken if it turns out that there is no evidence.... — anonymous66
I might not be heartbroken either, if it turns out that there is no evidence. And in any case, I don't expect ever (well, not in the next 2,000,000 years anyway) to find a wolf or a whale thinking about God, angels, infinity, souls, the great chain of being, or such topics.
Apokrisis point about grammar makes sense. A grammatical language seems to be required to think and talk about abstractions. Dogs do seem to live in the present--something people practicing Yoga strive to do. "Be present in the moment...." Hey, my golden retriever was an ace at that. At least as far as I could tell. For all I know, she wasn't just laying on the couch staring out the window;; she may have been communing with the Mind of God, or reviewing the various resentments I am sure she harbored. But I can't say.
Oliver Sacks wrote a book about sign language, and the dramatic impact it had on adults, particularly, adults who had recently learned it. Concepts that had been invisible before suddenly became possible. Their experience of time, for instance, was greatly enriched.
But, perhaps your (Bitter Crank) point was that there isn't much evidence now, but if people actively look for it, they might derive ways to find it? — anonymous66
Well yes, that was my point. My conception of "animal thinking" is that their thinking is rather simple. I'm well aware how easy it is to assign more "thought" to a pet than their behavior requires. As we establish our relationship with a puppy, for instance, dog and human are each learning how the other one operates. Dogs make good pets because their species interacts in groups just by nature. They have to learn how to do it, but they are well equipped. They are sensing, learning, and remembering, the same way a young child senses, learns, and remembers.
Some dogs, parrots, and primates have learned word lists, for instance. They can learn that the word "shoe" matches a shoe-shaped object. This genius border collie in Germany managed to learn 1000+ words (each for a unique object, which it was able to fetch on the basis of the spoken word]. This is outstanding performance for a dog, but it is the sort of things dogs do all the time. Include the world "walk" in a sentence, and the dog is likely to pick that word out and start agitating to go for one.
One of the things about animals learning language is that it doesn't seem to do anything for them. WE like teaching them, and WE think it is exciting to watch them learn and perform, and since the animals are rewarded frequently, they like it as long as the rewards last. But knowing 1000+ German nouns probably didn't enrich the dog's mental life. (Just guessing.) What our dog found life enhancing (going by body language) was getting fed, drinking water, being let outside on demand, going for walks, playing, and being scratched and petted. She had a stiff knee so she started soliciting scratching from us--which she found superior, apparently. She liked our furniture and our food a lot, and appreciated heating and AC. That's about it. She refused to learn commands (aside from speaking for food, sit, lay down, and shut up). No paw shaking, no rolling over, no sitting up, etc.
Our language makes anthropomorphizing almost inevitable. We ascribe thinking to animals when we say "she wants...", "she doesn't like...", "she looked disgusted about..." and so forth. Our language works on people, of course (reasonably well), and dogs are as anxious to please (more so, usually) as people. Interpreting their behavior as sentient just comes naturally. Hell, we ascribe sentience to our cars sometimes.