From teaching experience. IX. Entropy of the convex polyhedron

The article is devoted to the applications of the entropy category in the natural sciences, mainly in mineralogy and crystallography to describe the complexity of mineral parageneses and crystal structures. It is shown that thermodynamic, informational and statistical entropy, defined independently in different disciplines, do not copy each other. They are not recalculated into each other and agree at the level of general principles. Statistical entropy as a measure of the complexity of systems characterized by probability distributions of parameters is always their convolution with loss of information. As a scale of complexity, it is unevenly curved in different areas of the probability field. The article is dedicated to the 85th anniversary of the birth of N. P. Yushkin.