Branches of Philosophy

What are the Major Branches of Philosophy? What are the Minor Branches of Philosophy?

On this page we discuss the major and minor branches of philosophy and the different ways to understand and categorize them.

The major branches of philosophy can be denoted as: metaphysics (what is), epistemology (what we can know), logic and reason, ethics and morality, and aesthetics (beauty and art).[1][2][3]

Of these branches, metaphysics is the primary one. Metaphysics seeks to explore the true nature of reality in terms of any subject by asking questions like: “what is, what could be, and what ought to be?” Since philosophy itself can be described as “the study of…,” metaphysics at least covers the “study of what is, what could be, and what ought to be,” and very broadly speaking works as almost a synonym for philosophy in this respect (or at the very least, a synonym for all philosophies that deal with that which we don’t know for sure).

With that said, calling all of philosophy “metaphysics” doesn’t tell us much about what we are studying, so it helps to divide philosophy into branches.

There are a number of ways to divide and subdivide the branches of philosophy (AKA categories of philosophy).

The way above, where epistemology covers what we can know, logic and reason covers how rational systems work, ethics and morality cover actions and feelings, aesthetics covers beauty and art, and metaphysics covers every other unknown is one way to divide the major branches. However, we can also consider other categorizations.

Not only can we use different models for the primary categories (major branches), we can also consider minor branches (or sub-categories) of any of the major branches we define.

Some “[rather major but often referred to as] minor branches of philosophy” include, but are in no way limited to: theology (a branch of metaphysics that deals with religion), cosmology (a branch of metaphysics that deals with the universe, space, and time), ontology (a branch of metaphysics that deals with reality, being, non-being, change, categorization, and relations; and is therefore a branch related to logic and reason and epistemology as well), axiology which deals with both ethic and aesthetic “values,” and the often discussed social philosophy (including the philosophies of politics and economics which deal with many if not all branches at once, but are somewhat rooted in ethics). NOTE: Social philosophy, or political philosophy, is sometimes considered a major branch (and rightly so in my opinion).[4]

Other notable major-minor branches include the philosophy of language, the philosophy of lawthe philosophy of maths, the philosophy of mind, the philosophy of health, etc).

Further, and in general, each field of study in modern life (arts, sciences, etc.) and all their subdivisions essentially have a related field of philosophy. Speaking broadly, we can call these countless areas of philosophical study related to every subject possible “minor branches” as well.

This gives us minor “branches” (AKA categories of philosophical inquiry) like the philosophy of geometry, the philosophy of post-modern art, the philosophy of comedy, the philosophy of propositional calculus, the philosophy of moral sentiments, the philosophy of computers, the philosophy of medicine, the philosophy of U.S. law, the philosophy of group behavior, etc. Here, if you can study it, and especially if it is a category of inquiry that can be studied formally, it can rightly be considered a minor branch of philosophy… and that means we can get as specific as possible, discussing not just the philosophy of a TV show, but the philosophy of a character on a TV show for example (although you probably can’t get a PHD in that).

In other words, we take the tree of philosophy, then it branches out, and branches out, until we are studying (asking what is, what ought to be, and what could be?) about something very specific.

With all that said, to re-state this core point, there is notably no one way to express either the major or minor branches of philosophy (especially considering how some bleed together and how some branches are more “major” or “minor” than others).

For example, as an alternative to the above, we could consider the major branches to be 1. the one that deals with all physical things (the philosophy of the physical and aesthetic), 2. the one that deals with logical things (the philosophy of logic and reason), 3. the one that deals with all actions (the philosophy of ethics and actions), and 4. the one that deals with all sentiments and imagination (the philosophy of metaphysics and philosophy of moral sentiments).

Or, for example, we could divide into a two-fold divisions of 1. natural philosophy (that which deals with the nature of the physical universe, all being and even the logic related to it) and 2. moral philosophy (that which deals with ethics and metaphysical sentiments).

Or we could simply consider 1. all empirical philosophy and 2. all rational philosophy (using a mind/body, or a priori / a posteriori division).

Or, we could simply think of any subject under the sun (0r not) and consider it as having an “applied” aspect (applying what we know) and a “philosophical” aspect (an aspect of theory, asking “what could be?”).

Or, we could consider all of the above, like we do on our page of epistemological and ontological categorization.

Any division, popular or not, broad or meta, will have pros and cons. Further, there can be no “100% correct” system, because the meta-logical system of dividing things into categories is… a thing of metaphysics, epistemology, and logic and reason.

Despite the different ways we can approach categorizing the branches of philosophy, ultimately any system will point back to the same truisms (as in all cases we are simply studying “what is” and asking “what could be and what could be?” and using naming conventions to denote a field of inquiry.)

With all that in mind, we present an overview of philosophy in general, each major branch of philosophy (denoted commonly in different models), examples of minor branches, an explanations of different systems of categorization, and how to understand all this below.

TIP: If you look at another popular web page on the branches of philosophy, Introduction to the Five Branches of Philosophy by, or if you look at or wikibooks, you’ll notice that we are all essentially saying the same thing (but using slightly different models). This is speaks to the bottomline here. That is, the categories of philosophy are logically broken down into sections based on the questioning of different aspects of the human experience and subcategorized from there… but there is no one perfect place to draw divisions.

Branches Of Philosophy. A basic overview of the branches, see our more complete list below.

TIP: As noted, of the major branches, metaphysics is the main one. Speaking loosely, all philosophy is a type of metaphysics (where we can denote the study of anything as the philosophy of it, or the metaphysics of it, and denote two general categories as natural philosophy and moral philosophy). From this perspective epistemology and logic and reason are the metaphysics of rational ideas (related to language), ethics and morality are the metaphysics of morals and actions (related to mind and social systems), aesthetics is metaphysics of physical beauty, and metaphysics itself covers all lines of inquiry not considered (or at least not considered as applied science). Then, to subdivide, the metaphysics of physics covers theoretical physics, the metaphysics of physical systems covers cosmology, the metaphysics of being relates to ontology, and the metaphysics of spirituality relates to theology, etc. On this page the aim is to go beyond telling you about a given version of the branches (as that has already been done) and instead clue you in to the reality of philosophy in its original meaning, that is: the study of anything (as “to study” is to draw out “what is, what could be, and what ought to be.”)

How to Understand Philosophy: The Theory Behind the Major and Minor Branches of Philosophy

Philosophy loosely translated means “the pursuit of wisdom” or “the love of wisdom.” It isn’t about “knowing” (or thinking you know; that is sophistry), it is about the pursuit of knowing, even when we know we don’t (or can’t) know for sure.

To know, is to think about and ponder, to think about ponder is “to study.”

Another way to phrase this is that philosophy is by its nature asking “what is,” “what ought to be,” and “what could be?” And, logically speaking, this method of questioning can be applied to any subject.

Simply then, philosophy is the pondering of that which we don’t know for sure as it pertains to ANY subject.

With this in mind, more than giving each type of philosophy a name, we can understand that all philosophizing (all philosophical arguments, questions, and musings) about each art, science, mechanic of society, existence, etc can be categorized using logical, epistemological, and/or ontological systems and then refereed to as “a branch of philosophy.”

Thus, the term “branch” here simply means “a category in which we have placed philosophies that share properties.”

When we speak about philosophy generally, we use terms like “metaphysics,” “ethics,” “logic,” and “aesthetics,” grouping many branches together by common properties. For example of grouping by those specific terms, metaphysics gets grouped by its relation to “feelings” (including sentiments, intuitions, and imagination), ethics its relation to actions, logic its relation to ideas, and aesthetics its relation to physical objects/beings. then we can consider sub-categories, like treating imagination and sentiments differently in metaphysics, or considering a metaphysic physical mix like cosmology.

With that in mind, when we speak about philosophy more specifically, we can use terms like “theology,” “ontology,” and “cosmology” (to denote specific categories; here the philosophy of religion, the philosophy of being, and the philosophy of the universe respectively).

Then, when we zero in we can consider the many different subdivisions of each field (again, grouping them by common properties; conceptual or real), we get minor branches like political philosophy, philosophy of language, philosophy of the mind (psychology), philosophy of exercise, philosophy of economics, philosophy of baking, etc.

Then going even deeper, we can consider philosophy of a specific TV show, or the philosophy of making a great vegan taco, etc., etc.

Because of the way this works, there is no perfect sub-division, just many useful ones (some commonly agreed on, some not).

Want to consider the philosophy of Internet Explorer 6? That is simply a subdivision of philosophies related to computers, business, and psychology (which are related to a number of major branches including logic and the social philosophies).

Want to learn about philosophy in general? Then look to metaphysics.

Want to study ethics as it relates to law? Then you don’t just want to study ethics, you want to study the subdivision of social and ethical philosophy, the philosophy of law (either modern or historic, either general or specific to a field of law).

Here, with all this complexity in mind, one could argue that the underlying concept of philosophy and the nature of each subject studied is more important than the exact naming of divisions, their hierarchy, or their categorization into “branches of philosophy.”

What is is what is (ontologically speaking), the naming rights of the branches is little more than convention.

Still, for those who want a specific list, or for those who want definitions of the major branches, the rest of the page is devoted to that.

TIP: Above we discussed “the philosophy of the branches of philosophy;” doing this is a thing of metaphysics, epistemology, ontology, and logic and reason… because we are working with pure ideas, applied to the nature of things as they are, to find out what we can know, using a logical system of categorization.

What is Philosophy?: Crash Course Philosophy #1: A great overview of philosophy by CrashCourse. The other great resource for YouTube philosophy is The School of Life. These are great resources.If you like them, remember that we introduced you to them and you can find lots great supplemental content on our site.

FACT: We used to call science “natural philosophy,” while metaphysics was the book that comes after physics. Before the scientific revolution, most academics were a considered to be a branch of philosophy including everything from science, to element theory, to theology.

Documentary – Western Philosophy, Part 1 – Classical Education.

TIP: To understand the basics of western philosophy you only really need to read a few philosophers. Start with Plato and Aristotle in the 300s BC., two prolific Greeks, one who laid the groundwork of modern western philosophy (Plato) and one who wrote books on each of the major philosophies (Aristotle). Skip ahead to the scientific revolution with Descartes in the 1600’s who sums everything up at that point. Do a quick overview of Locke in the same period as Descartes, and then Kant in the early 1700’s. Review Smith and Marx for a look at economic and political theories, then maybe study Nietzsche and Popper to see how their theories expand on that. It isn’t that they are the only important ones (in fact that list was particularly skimpy); it is that philosophers tend to be versed in general knowledge with each having read the greats before them. So you’ll see a lot of recurring themes, and importantly for our conversation, you’ll be able to spot the types of philosophies employed.

TIP: Rarely does a line of questioning only relate to one area of philosophy. Try to study the philosophy of mathematics, and it can easily cross over into theoretical physics. Try to study political theory, and you’ll like find yourself thinking about the philosophy of language, the philosophy economics, and epistemology. Philosophy, more than being about branches or sub-branches, is about going beyond what we know for sure.

What are the Major and Minor Branches of Philosophy?

If one wanted to subdivide philosophy into major and minor branches, thus giving a hierarchy, one way to do it would be like this (NOTE: this is not an official way, I don’t think there is one, and this is not the only way):

  1. From one perspective, one could call consider all philosophy to be “metaphysics.” After-all, both philosophy and metaphysics question that which we don’t know for sure. If we aren’t talking about pure empirical applied sciences “a posteriori,” and we aren’t talking about the pure formal nuts and bolts of logic, we are essentially talking about metaphysics to some degree. The problem here is that natural sciences, logic, ethics, and metaphysics are all very different areas of study; so more nuance is helpful (otherwise we are just really using philosophy and metaphysics as synonyms).
  2. With the above in mind, perhaps the simplest and most useful categorization of philosophy is: 1. natural philosophy (physical science and logic) and 2. moral philosophy (ethics and metaphysics). From this perspective all fields of study are types of philosophy, all “branches” noted on this page can be placed in either two or for categories, and then the use of knowledge is simply “practical application” of philosophy.
  3. That said, to classify the major branches of philosophy into the common “5 major branches of philosophy” we can denoteMetaphysics (all questions “a priori” that discuss that which we can’t know for sure including questions of God, free-will, morals, and sentiments), Logic (including epistemology and ontology; the philosophy of “what we can know” and “how we can know it”), Ethics (the philosophy of conduct and human action; under which many social philosophies fall), Aesthetics (and the philosophies of the natural sciences; Aesthetics is specifically focused on art and beauty, qualities of physical things, but loosely this category can be said speak to the sciences of physical things and thus it includes all empirical philosophy, “synthetic propositions a priori,” and fields like theoretical physics as well), Social (political, psychology, economic, etc; philosophy related to human interaction and its mechanics, which sort of mashes up all other major branches). TIP: This is a variation of the major branches offered above which was denoted as metaphysics (what is), epistemology (what we can know), logic and reason, ethics and morality, and aesthetics (beauty and art) offered above. There is no one way, so I’ve offered two ways to help illustrate this. Do we consider epistemology to fall under logic? Do we consider social philosophy to fall under ethics? Do we consider ethics to contain subjects of morality, or do we consider metaphysics to contain it? Those questions don’t have a definitive answer!
  4. Then, the minor branches of Philosophy are: An undefinable list that includes the philosophy of education, language, mind, religion (theology), being (ontology), cosmology, science, art, math, society, economics, laws, politics, games, etc, etc, etc.
  5. We should also note that: We could define hierarchies even in the major and minor branches. The study of Christianity is for example a sub-division of theology in general and existential philosophy a subdivision of ontology, aesthetics, and social philosophy…. meanwhile, as noted, this is all essentially a sub-division of metaphysics.

In other words, we can most certainly categorize philosophy to denote hierarchy, and doing so can be very useful, but there is no one perfect way to define the branches.

With all that said, to offer concrete advice, in my opinion, separating the branches as they pertain to the physical (empirical), logical (reason), ethical (philosophy in-action), and metaphysical (pure philosophy) is a good start.

This essentially matches up with philosophy as it is understood in the modern day, and is based on ontological and epistemological theory rooted in Greek thought (where study was divided into physislogos, and ethos, … leaving us only to denote Aristotle’s metaphysics as a fourth category)… of course Metaphysics is in many ways philosophy itself… and, well, this is where it gets complex. Anyway, on to definitions (which should help clear up some lingering questions).

A model showing logic, physics, ethics, and metaphysics as “spheres of human understanding”.

On the Categorization of Philosophies in Other Ways

Above we presented a more complete list of widely accepted modern categories (just like we touched on in the introduction), next let’s explore what it means to “categorize philosophies” AKA the philosophy of categorizing philosophies, a logical system of metaphysics (as eluded to above, to categorize is a thing of convention, but the philosophy itself is not convention, it is a naturally occurring name for that which arises from sentient beings studying being and non-being and considering “what is and what could be” in terms of any specific aspect of that broad system of being and non-being):

The most important thing to understand is that a system of categorization (be they the branches above or this next system we will focus on) is just that, any given system is “A system” not “THE system.”

Below is a system of categorization that we use on our site, defined on our page “a system of categories of being and knowledge,” that can be applied to philosophy with great accuracy and is rooted in Greek tradition. That system is:

Aesthetics, the branches of ethics that deal with morals, and the branches of metaphysics that deal with the physical like cosmology can be categorized as beingof the physical,” the aspects of ethics and morality that deal with actions are “of the ethical,” the branches that deal with pure logic and reason are “of the logical,” and the categories that deal with the sentiments, intuitions, and imagination are “of the metaphysics.”

Spheres / Categories Empirical / Material (Based on Experience) Rational / Formal (Based on Ideas)
Natural Philosophy (Based on Experience) Physical Philosophies (Empiricism; the philosophies of all physical things) Logical Philosophies (Pure Logic and Reason; philosophy of rationalism)
Moral Philosophy (Based on Ideas) Ethical Philosophies (Philosophy-in-Action; free-will) Metaphysical Philosophies (Pure Philosophy of sentiments and imagination)

These “four fundamental categories” derived from the Greek concepts of physislogosethos, and pathos (here consider that Aristotle wrote a book on each category physics, logic, ethics, and metaphysics) can be used to categorize all the philosophies, natural and moral in a system.

Although I personally like this system that bridges the gap between Aristotle and Kant, it is hardly the only system out there.

With that in mind the video below does a good job of backing up the point we hopefully just made, that is: there are different logical ways to categorize the philosophies.

Every subject under the sun, real or imagined, gets a philosophy, and consequently there are as many ways to categorize them as there are ways to categorize all systems ontological and epistemological.

Philosophy in its most broad definition simply study of anything, natural or moral, real (being) or not (non-being).

We can go broad and say “the philosophies of the physical (empirical), of the rational (logic), of actions (ethics), and of sentiments and imagination (metaphysics)” like we did above with our Greek inspired system… Or we can get meta and discuss the metaphysics of normative ethics and how it relates to meta ethics as a field of metaphysics as expressed in terms of formal logical equations.

Or, we could do anything in between (or even use a mix of systems and consider “transcendental categories” or divide into continental and analytic, or western and eastern, etc, etc, etc).

In summary, and we’ll detail this all more below as we present more systems, philosophy is simply us questioning a subject (broad or refined).

We can thus categorize it in many different ways, like we do with our fundamental categories of being and knowledge, or like they do in the Map of philosophy below, or like they do in the branches video above, or like we do in the branches listed on this page, or like they do with the categories they offer you a PHD in in school (a PHD is a degree as a doctor of philosophy in a given subject).

The Map Of Philosophy. A basic overview of the branches, see our more complete list below. Notice the colors they use in their map. Yellow for logic, green for the physical, blue for metaphysics… these colors are consistent with western element theory and astrology. Are they convention or not? We won’t muse on that question of metaphysics, but let us just say, I know I did not pick them at random for our theory. The colors like the subjects have meaning. All philosophy is the art science of moving toward knowing and exploring that meaning.

TIP: If you want another viewpoint on how to group the major branches, see Introduction to the Five Branches of Philosophy.

A List of the Branches of Philosophy With Definitions – Explained Simply

With this in mind, below is a list of some important major and minor branches of philosophy as they are understood today:

Metaphysics – The study of being, The book that comes after physics, the study of what is there and what is it like. If we take Einstein, Newton, and Michio Kaku’s theories, and then go one step further to look at what is beyond the laws of motion, mass-energy, and string theory, then we are musing on metaphysics. Literally, “meta” coupled with “physics”, meaning “what is beyond physics.” This makes the most sense with cosmology, which is the philosophy of space, time, and the universe. Metaphysics also studies determinism versus free will, the duality of mind and body, and other aspects of being, including religious concepts (ontology and theology, noted below).  If we consider this broadly, then metaphysics implies the philosophical study of the physical universe, so it is all questions about reality that we can’t answer with science. Metaphysics can broadly contain all the other philosophies (but even the Greeks considered ethics, logic, epistemology, and aesthetics separately, and we still do today). If you think about it, when we consider the nature of being, it is metaphysics when we go beyond what we can observe directly.

Epistemology – The study of what we can know, the study of truth. Descartes said we couldn’t trust our senses or what we read, all we can know is “I think therefore I am.” On we try to define what is “a fact” and what is “myth” and label things as true or untrue. Socrates said, “all I know is that I don’t know”. The scientific method is a rule-set with which we can debunk our theories. What is the truth? How do we know? How can we know we know? Why do we believe it? How do we perceive it? To even answer any of those questions, we really have to consider ontology (the study of being). See a theory of human knowledge for an epistemological and ontological theory.

Ontology – The Philosophy of being. Ontology is the study of the nature of being (and non-being and change) and related “categories” of being and their relations. Plato defined the basics as being, non-being, and change. Aristotle’s Categories is a foundational work of Ontology which seeks to categorize the states of being and the relations of terms. This aspect of philosophy naturally bleeds into epistemology, logic, and reason (in terms of what we can know) and into theology (in terms of the meaning of being).

Theology (and to some extent Ontology) – The philosophies that deal with God and religion. Both ontology and theology can be filed under metaphysics; both explore the concept of God in some way. The main difference is theology assumes there is a God as a starting point, and ontology doesn’t (it considers the nature of being, and therefore considers the possibility or impossibility of God). Ontological and Theological arguments are typically paired with other philosophical lines of reasoning.

Logic (and Reason) – The study of… logic and reason. In logic, arguments of rhetoric, justice, law, political philosophy and importantly mathematics are mixed. In ways, logic is the math of philosophy (or often, when dealing with rhetoric and politics, the social science of philosophy). We won’t consider how to organize a society based strictly on morality; we will try to use critical thinking, deductive reasoning, and structured arguments. We can say logic is the philosophy of mind, while ethics is the philosophy of the heart. Almost every theory can be categorized under logic, as logic is almost always employed when trying to prove philosophical arguments or explore philosophical problems. Learn more about how logic and reason work.

Ethics – The study of Morality, Human Action, and Conduct. Ethics is probably the most important and undervalued philosophy in the modern day. It is just what it sounds like, the study of what is right, moral, ethical, and good. The Supreme Court of the United States and the Legislative Branch is meant to be a branch of government rooted in the concept of ethics. We can apply ethics to the self, interpersonal relationships, large groups, and even states. When we consider political and economic philosophy we focus on ethics. Many modern philosophers like John Rawls try to argue for justice and ethics without using ontological or theological arguments, but even the forefathers of philosophy like Socrates, Plato, and Aristotle argued for ethics. If we consider the point of life happiness, then we can see the city-state (and thus political science) as the ultimate vehicle with which to spread goodness and happiness in society. When we consider ethics, we think of concepts like good and bad, right and wrong, and virtue and vice. Learn more about virtue theory.

Political, Economic, Legal, and “Social Philosophy” – The study of how to organize a society. Many would argue that the most important philosophies are those that have real world application. No lines of reason have more influence on society than political, economic, and social philosophies. If you think of the impact that philosophers like Marx, Smith, Kant, and Locke had on cultures around the world, you can see how this area of philosophy is one of the greatest importance. Almost all of the great thinkers are most widely know for the political, economic, legal, and or social philosophies they have presented. The United States of America is very literally founded in the political, economic, and or social philosophies of the scientific revolution and enlightenment period. This is clear from the wording of the Constitution, Declaration of Independence, and even from the symbolism on the back of the dollar bill. Given this, we should do away with any ideas we may have about philosophy “not being real” or “not being important”. Concepts like the freedom the pursue happiness, life, and liberty in a just society that values enlightenment are philosophical in nature. This line of thinking can also include philosophies of groups such as feminist philosophy.

Aesthetics – The study of beauty and art. What makes something beautiful? This simple question is its school of philosophy. It is the perception of art and culture as it pertains to aesthetic qualities rather than more anthropological or functional qualities. Aesthetics can also be called Esthetics. NOTE: When no other context is give, the aesthetic is about beauty and art. However, from a broad lens aesthetic just means “the empirical physical realm.” Thus, the aesthetic can include physics, natural science, cosmology, the early pleasures (vices), and more. It really depends on context.

Tamar Gendler: An Introduction to the Philosophy of Politics and Economics.

TIP: Sometimes aesthetics is combined with ethics, politics, and other “related” aspects as Axiology.

Philosophy of Mind – The study of self and group thinking. We can break off from metaphysics and the study of being and consider the study of mind. This encompasses individual, interpersonal, and group psychology and theories of group decision making and collective intelligence.

Philosophy of History, Language, and the Humanities – When we study the philosophy of the humanities or history, but not from an aesthetic viewpoint it can be labeled its type of philosophy. We can study filmmakers and film history by looking at the philosophy of film, or we can do the same thing for music. When we study the semantics, structure, or use of language it is the philosophy of language. We can consider how rhetoric relates to political philosophy and philosophy of the mind.

Philosophy of other Arts and Sciences – We can study the foundations, methods, and histories behind any field or pop-culture item. There are no limits when we muse on a subject we partake in a philosophy of it. If we want to muse on the philosophical nature of Pez dispensers, we are at the very least partaking in Pez philosophy. We can consider the beauty of Pez, what we can know about Pez, the philosophical economics, and politics of Pez, etc. It won’t always have a name, but by knowing how the branches of philosophies work, you’ll have a pretty good idea of what line of reasoning you are following.

TIP: Eastern philosophy can be categorized and understood through the lens of western philosophy, or it can be explored on its own merits. To keep this page readable we won’t explore ancient philosophy or Eastern philosophy. You can learn more about philosophies and philosophers at Wikipedia.

EASTERN PHILOSOPHY – Lao Tzu. Here is an Eastern philosophy starter kit. Buddha, Lao Tzu (the Tao), and Confucius should be your first stop.


  1. Branches of Philosophy
  2. Divisions of Philosophy
  3. Introduction to the Five Branches of Philosophy
  4. Philosophy

"The Branches of Philosophy Overview" is tagged with: Epistemology, Ethics, Logic and Reason, Metaphysics, Morality, Philosophy of Language, Philosophy of Law, Plato. Aristotle. and Other Greek Philosophers, Truth

What do you think?

Samuel ojja on

Truly, its very interesting course to take I like philosophy.