no, but `$ yes "a cat is an animal"` does (if you know how to interpret it)
What really happened here is that a human wrote down, "a cat is an animal," and then another human read it, understood it, and believed it. And so the knowledge moved from one human to another. `yes` was only a conduit for that information to travel through.
If something was a conduit for knowledge wouldn't it make sense that it would have at some point contained the knowledge? The knowledge is stored into it by one human and extracted by another human.
It's ability to produce text containing true statements isn't sufficient evidence to conclude that it has beliefs, and it's easy to find cases where it contradicts itself (eg, if you play around with the wording you can find a prompt where it tells you that solving the trolley problem is a matter of harming the fewest people but proposes a solution that harms the most people). I take that as an indication it's primarily regurgitating text and rearranging the prompt rather than applying knowledge (which, to be clear, is useful for a number of tasks).