This creates an interesting paradox.
If you take a wild animal, especially a predator, they do a lot of “non-thinking thinking”. Kind of hard to describe, yet they do not get bogged down in figuring out a best course of action, but use their prejudices and “best guesses” to achieve their outcome.
Even humans can access this somewhat, as it has been noted that while most people cannot accurately guess something they can rationally think about, they are very good at guessing *about* the right answer.
For example, if, in no particular order, you put three piles of pills on a table, one with 90, one with 100, and one with 110, you can probably guess which is which, as well as *about* how many there are in each of them. (”About 100 in each”.)
However, “thinking about thinking” gives humans some odd advantages, while costing us the speed of “non-thinking thinking”. The most important of these advantages is the ability to use “abstracts”.
The king abstract is mathematics, but it is far from the only one. Others include universally understood pictures (illustrations), for example even something as simple as a stick man figure. If you learn that it represents a man, from then on, it always represents a man, and nobody needs to explain it to you if you see a similar picture in the future.
Another great abstract is language, both non-verbal and verbal. Even many animals can learn what spoken human words mean, some animals even learning the context of them; even though only a few, like parrots, can not only mimic them, but do it in context.
And a few, like some gorillas, can use a pictographic language to communicate. And, it’s been noted, even teach language to their offspring.
Another superb advantage of “thinking about thinking” is planning. Planning is an incredibly ordered and straightforward abstract. To the point that the planning outline formalized by Sun Tzu, in the 6th Century B.C. is very similar to that used by all modern armies today.
If you really want your mind messed up, watch the PBS show “Nature: What Plants Talk About”.
*Everything* is “thinking”.