Michael Egnor looks at such claims. Including apes as co-authors on a primatology research paper created quite a stir—among humans.
Much in the article is of interest, if you can bear it, but I’ll discuss here the first sentence from the abstract, offering a commentary:
“Modern Western society assumes that nonhuman animals do not possess an episteme comparable to humans; this presumption is used to exclude nonhuman species from knowledge-making and practices that intimately affect animal lives.”
Modern Western society assumes that nonhuman animals do not possess an episteme comparable to humans because nonhuman animals do not possess an episteme comparable to humans. The proof of this assumption is simple: nonhuman animals have not taken any position in this debate, nor have they published their own review articles in Project Muse, because, well, they do not possess an episteme comparable to humans.
In plainer language, non-human animals don’t and can’t think abstractly.
Michael Egnor, “Can animal minds rival humans under the right circumstances?” at Mind Matters News
It’s not clear that naturalism commits a person to such an obviously false belief but some are prepared to go that far.
More on animal intelligence:
Do animals truly grieve when other animals die? Yes, but “death” is, in some ways, an abstraction so there are only some things they understand about it. For example, the dog Hachikō’s lifelong devoted vigil at the train station is touching in part because he could not know that his human friend had actually died. (Denyse O’Leary)
The real reason why
only human beings speak. Language is a tool for abstract thinking—a necessary tool for abstraction—and humans are the only animals who think abstractly (Michael Egnor)
The idea that animals think as we do dies hard. But first it can lead us down some strange paths. And it seldom does much for the animals. (Denyse O’Leary)
and
Researchers: Apes are just like us. And we’re not doing the right things to make them start behaving that way… In 2011, we were told in Smithsonian Magazine, “‘Talking’ apes are not just the stuff of science fiction; scientists have taught many apes to use some semblance of language.” Have they? If so, why has it all subsided? What happened? (Denyse O’Leary)