On the origin of concepts

There are fundamental, universal concepts connecting everything you read, think, see, and do. These concepts (or ideas) are the essence of human knowledge.

Philosophers spent a few millennia debating this ancient theory. Mostly asking, “Where do these concepts come from?”

Plato argued for a world of these concepts above this reality. Imagine a pristine museum in the sky where the perfect forms of justice, cupness, and redness live on tidy shelves that are never dusty. Except of course for the shelf with the pure form of dustiness.

Aristotle gave Plato's ideas a new metaphysical address. He said they exist in physical objects or persons themselves. So your shirt doesn't take its shade from the perfect essence of redness in the sky. Instead that perfect redness inhabits your shirt (and others like it).

Augustine came along and moved the concepts to a new location: the Mind of God. A logical move since concepts do seem to require a mind. If these ideas are indeed eternal and unchanging, it makes sense that they would live in the mind of the eternal, unchanging God.

In the 14th century, William of Occam (and his nominalism) effectively called off the search, announcing that (surprise!) the ideas were only in our heads the whole time. They are subjective, not objective. Particulars, not universals. We don’t discover them; we invent them.

Of course, a lot of the debate has been theoretical. But the practical problem persists. Our minds bump into abstract realities just like our bodies bump into physical ones. They really do seem to be as real as rocks. They might be more real than rocks.

Are you skeptical about a pure, ideal essence of mud, dust, or cups? I get it. What about Justice? Beauty? Love? I'm not convinced anyone really believes these ideas are entirely subjective.

Or is the nature of these ideas (and others) determined by something outside of us?