In her influential 1999 book, The Meme Machine (chapter 5) Susan blackmore raised three important problems about memetics. Each problem was titled as follow: "We cannot specify the unit of a meme", "We do not know the mechanism for copying and storing memes", "Memetic evolution is Lamarckian". These three problems are still largely relevant today, as progress with memetics is proving to be slow. However I think my proposed views on memetics, which I call the code model, could help answering or clearing up some of those points.
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