Stravinsky is referring to Eugenio D’Ors’s phrase (translated from Spanish): “What is not tradition is plagiarism.” I’ll admit that I wrestled with this idea considerably. Let me try rationalizing it:
To what extent do you believe that our creations are original?
In the above phrase, the word ‘tradition’ is being used to describe the transfer of all knowledge, ideas and experiences from the past to the present. All of our creations may be original, but they’re fully reliant on a lineage of ideas that have been passed on through time, from generation to generation. In this sense, the word ‘traditional’ is all encompassing; nothing can escape it, no matter what.
This means that there’s no such thing as “breaking from tradition.” The notion of breaking from a tradition could only be realized through tradition. In other words, you’d be following a tradition of breaking from tradition!
What about plagiarism?
Plagiarism, in this context, refers to an exact copy and transfer of any knowledge, idea and experience from the past to the present. This is impossible. It’s inconceivable to recreate the conditions of an original idea, let alone its transfer and subsequent effect on future ideas. The only way this could happen is if we froze the accumulation of knowledge through time. That would be breaking from tradition!
A tradition of plagiarism then, is a paradox. Plagiarism is the antithesis of tradition, just as cloning is the antithesis of biological evolution. They can’t co-exist.
In this sense, Eugenio D’Ors’s phrase is actually quite humourous! It takes advantage of this dichotomy to stress the broad implications inherent in tradition. Namely, that tradition is inescapable.
Further reading: Chapter 11 from Richard Dawkins’ The Selfish Gene. “Memes: the new replicators.” (Link)