The human body is studied by three sciences: anatomy, physiology, and hygiene. Anatomy studies the structure of the body. Physiology studies the functions of organs and of the body as a whole. Hygiene studies the conditions necessary for preserving and strengthening health. Among these three sciences, anatomy is traditionally considered the hardest to understand both in school and in higher education. There is a saying that anatomy can be mastered only by rote memorization. Memorize, memorize, and memorize again! Otherwise, no way! Yet that’s not true. If we view the human body as a single system rather than a set of separate organs, it immediately becomes clear how logically it is arranged. You don’t need to cram—you need to think: understand the purpose of each organ, see the connections between organs and systems, and so on. With this approach, you won’t have to memorize anything.