The four branches of philosophy include metaphysics, epistemology, axiology and logic. Metaphysics is concerned with the nature of being and reality, and aims at addressing the interest of a man about the nature of God, substance, space, truth and the origin of the universe among other aspects of existence and reality. It has three subcategories, namely cosmology, which outlines the explanation about nature of the universe together with its origin and development, ontology, which explains the meaning of existence and the spirit of God, and teleology, which addresses the question of the existence of purpose in the universe. Generally, metaphysics describes the relationship between the body and the mind, and the concern of freedom. Epistemology is the branch which deals with the study of knowledge. It seeks to answer questions concerning the definition of knowledge, where it came from, and how humans obtain knowledge. It is subcategorized into a posteriori, which means that humans merely acquire knowledge after having relevant experiences, and priori, which means that humans only know things before they have experiences (Brightman 5).
Axiology is a branch in psychology that deals with the investigation of the nature of values and the establishment of value judgment. It comprises two categories. These are ethics and aesthetics. Ethics defines rightfulness in the society. Aesthetics is the consideration of what is beautiful and what is ugly. Logic is concerned with the treatment of relation of ideas systematically. It differentiates between valid reasoning and fallacious thinking. It has four categories. These are induction, deduction, syllogism and dialectic. Induction is reasoning by inferring a principle from a particular situation to a general conclusion. Deduction is reasoning from a general principle to a specific scope of that principle. Syllogism is an argumentation where the premise provides a conclusion. Dialectic is the means of establishing the truth starting with an assertion to a denial (Fullerton 3).