To define the subject-matter of Marxist philosophy we must examine the range of questions it studies and find out what sets it apart from other sciences.Throughout the many centuries of the development of philosophy its subject-matter has changed constantly. At first it embraced all the knowledge accumulated at the time - knowledge of the world as a whole, of its separate objects and phenomena, the Earth, man, animals, minerals, etc. Then as production developed and scientific knowledge was accumulated, the particular sciences separated into such individual branches of knowledge as mechanics, physics, chemistry, geology, and history. The dozens of branches of sciences in existence today study the most diverse spheres of reality.The main subject-matter of Marxist philosophy is the solution of the fundamental philosophical question, the relation of consciousness to being. As we already know, all philosophical systems must answer this question, but the only completely scientific, correct , and consistent answer is furnished by Marxist philosophy.The philosophy of Marxism is called dialectical materialism. It materialist because in solving the fundamental question of philosophy it proceeds from the premise that matte and being are primary and consciousness is secondary. It recognizes the materiality and knowability of the world, and studies the world as it really is. Marxist philosophy is dialectical, because it examines the material world in constant motion, development and regeneration.