It might be amusing for people to see the full context as I replied to Bodo: Serge Lang used it in his Addiison-Wesley text: " Algebra" in the first(?) 1965 edition. On page 105 after the chapter on Homology, the following appears: "EXERCISES: Take any book on homological algebra, and prove all the theorems without looking at the proofs given in that book. Homological algebra was invented by Eilenberg-Mac Lane. General category theory (i.e. the theory of arrow-theoretic results ) is generally known as <italic>abstract nonsense</italic> ( the terminology is due to Steenrod)."