Logic is the science and art of correct thinking. It attempts to codify the rules of rational thought. Logicians explore the structure of arguments that preserve truth or allow the optimal extraction of knowledge from evidence. Logic is one of the primary tools philosophers use in their inquiries; the precision of logic helps them to cope with the subtlety of philosophical problems and the often misleading nature of conversational language. 2. Ethics
Ethics is the study of the nature of right and wrong and good and evil, in terms both of considerations about the foundations of morality, and of practical considerations about the fine details of moral conduct. Moral philosophers may investigate questions as sweeping as whether there are such things moral facts at all, or as focused as whether or not the law ought to accord to rape victims the right to an abortion. 3. Metaphysics
Metaphysics is the study of the nature of things. Metaphysicians ask what kinds of things exist, and what they are like. They reason about such things as whether or not people have free will, in what sense abstract objects can be said to exist, and how it is that brains are able to generate minds. 4. Epistemology
Epistemology is the study of knowledge itself. Epistemologists ask, for instance, what criteria must be satisfied for something we believe to count as something we know, and even what it means for a proposition to be true. Epistemology is sometimes referred to as the “theory of knowledge.” 5. Axiology
Axiology is philosophical the study of value; the investigation of its nature, criteria, and metaphysical status. More often than not, the term "value theory" is used instead of "axiology." 6. Aesthetics
Aesthetics is the study of value in the arts or the inquiry into feelings, judgments, or standards of beauty and related concepts. Philosophy of art is concerned with judgments of sense, taste, and emotion.