Mathematician studied for centuries the abstract problem of drawing tangents to curves before Newton finally discovered what the subject really is about — rate of change.
It is a well-founded historical generalization that the last thing to be discovered in any science is what the science is really about.
Men go on groping for centuries, guided merely by a dim instinct and a puzzled curiosity, till at last some great truth is loosened.
— An Introduction to Mathematics by Alfred North Whitehead