This can be shown, for example, in chicken sexers. Chicken cloaca all look the same to most of us. But once you've learned for to distinguish the two sexes, they actually look different to you.

But any beginner art student knows the drawback of this. When you see a face, your brain sees it as a set of "face symbols." You then draw a set of "face symbols," and your drawing looks like a bad cartoon of a face.

Becoming an artist requires turning off the part of the brain that turns a face into face symbols, and being able to see the things for the thing it really is.

It is Paul Valery, but per Adrian Kohn's A Way to Look at Things by Not Forgetting Their Names, Valery may be (intentionally?) misreading Blaise Pascal just to get a jibe in. See footnote 3, bottom of page 11: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2674801

That is, the mechanical effort of forming notes on an instrument and reading them in and then playing a song is replaced by feeling the tune.

Once I've owned a piece of music, I can goof off with the tempo, try some variations, put in some mood.

In a word: jazz.

As an aside, this may help explain why neither jazz nor this sort of thinking is popular. There is much effort involved in hoisting oneself up to this level of skill.

"Thus everybody has certain rules according to which he acts in dealing with his tailor. These rules are, we will grant, soundly based on genuine experience ;and by acting on them a man will deal fairly with his tailor and helps his tailor to deal fairly by him. But so far as he acts according to these rules, he is dealing with his tailor only in his capacity as a tailor, not as John Robinson, aged sixty, with a weak heart and a consumptive daughter, a passion for gardening and an overdraft at the bank. The rules for dealing with tailors no doubt enable you to cope with the tailor in John Robinson, but they prevent you from getting to grips with whatever else there may be in him. Of course, if you know that he has a weak heart, you will manage your dealings with him by modifying the rules for tailor-situations in the light of the rules for situations involving people with weak hearts. But at this rate the modifications soon become so complicated that the rules are no longer of any practical use to you. You have got beyond the stage at which rules can guide action, and you go back to improvising, as best you can, a method of handling the situation in which you find yourself."

--

From the autobiography of R.G. Collingwood. His writings often have the theme of trying to understand particular instances of a thing on its own terms, only generalising into abstractions when seeing some quality in crowds of individual instances. I've rarely regretted that same approach when it comes to abstraction in code/software, but have regretted premature abstraction many times.

--Richard P. Feynman