On the occasion of the 100th anniversary of the publication of V. Lenin's book Materialism and Empiriocriticism, various notes on the margins and reading comments related to the old controversy of Marxism and positivism have been collected in a single text, along with a summary of the position of Unism on this range of problems. A kind of a book, without any overall concept, with no special design and no pretence for completeness. Just the flow of consciousness. This might come as handy to some people as anything else.