“Most people shy at the very word “abstraction.” It suggests to them the incomprehensible, misleading, difficult, the great intellectual void of empty words. But as a matter of fact, abstract thinking is the quickest and most powerful kind of thinking, as even an elementary study of symbolic logic tends to show. The reason people are afraid of abstraction is simply that they do not know how to handle it. They have not learned to make correct abstractions, and therefore become lost among the empty forms, or worse yet, among the mere words for such forms, which they call “empty words” with an air of disgust. It is not the fault of abstraction that few people can really think abstractly, any more than it is the fault of mathematics that not many people are good mathematicians.”

– Susanne K Langer: An introduction to symbolic logic, Third edition. Chapter I: The study of forms, p 34. Dover, New York 1967.