There are dozens, if not hundreds of different philosophical schools of thought in existence today. As a subject matter, philosophy covers such a wide range of material that it necessitates a variety of different theories and approaches. Some schools of thought only existed for a brief period of time, while others lived on for centuries. Some have been incredibly influential for different societies or time periods, while others began and then quickly fell into obscurity. However, even certain theories that no longer hold true by contemporary cultural and scientific standards can offer insight into the cultures and thought-processes of the past.
When analyzing different philosophical doctrines and movements, one must examine them with an open mind. Different belief systems and cultural circumstances apply for different philosophers. Appreciating these differences helps scholars and students understand the mindset and underlying principles guiding different philosophical movements. For example, many of the beliefs held in Ancient Greece influenced the philosophy of the day. However, by today’s standards, many of the religious and mystical beliefs seem archaic, or even intellectually backwards. However, this does not invalidate the original arguments and theories. The logic presented by philosophers like Socrates, Plato, and Aristotle is just as sound and valid today as it was in ancient times. The same principle holds true for other philosophical schools of thought throughout history.
It is difficult to examine the history of philosophy in its entirety, as there are simply too many important figures, theories, and influences to count. However, there have been certain schools of thought that stand out from the rest, either due to their impact on the history of Western culture or the intellectual genius involved in crafting them. The following list seeks to highlight some of the most influential schools of thought throughout the course of Western philosophy.
The school of Empiricism focuses on knowledge and how it can be obtained. More specifically, Empiricists assert that knowledge must come about through sensory experience and observation. Empiricism links to the development of scientific research, which also relies on empirical evidence when formulating new ideas and testing hypotheses. Empiricism stands in contrast to Rationalism, which elevates a priori knowledge and reasoning above observation. Though Empiricism has existed as a general theory in philosophy since ancient times, it did not become a recognized school of thought until sometime during the Renaissance era. Some of the earliest adopters included Thomas Hobbes and Frances Bacon, though John Locke and David Hume also popularized the movement in their respective writings. Despite its popularity, detractors argue that Empiricism does not properly account for innate knowledge and the objectivity of reason.
In stark contrast to Empiricism, Rationalism views reason as the only source of true knowledge. In this school of thought, existence is seen as inherently structured, and therefore capable of being understood through reason. If existence is structured, and reason can be used to understand this structure, then it follows that reason is a kind of innate knowledge regarding the nature of being. Rationalists such as Aristotle, and later Descartes and Spinoza, did not dismiss empirical or sensory evidence outright, but did not always see it as a necessity for finding the truth.
Spinoza put his own belief in the superiority of reason to the test in his famous work, A Short Treatise of God, Man and his Well-Being. In this treatise, Spinoza works from a small set of presuppositions and, using reason alone, forms an argument around the existence and nature of God. However, Empiricists counter the claims of Rationalists like Spinoza, citing the insufficient nature of reason, especially when compared to the observational powers of the senses.
Idealism concerns itself with the nature of reality. Though it deals with both metaphysical and epistemological arguments, the basic assertion among Idealists is that reality, inasmuch as we can know it, does not exist outside of the mind. Everything that can be sensed is a construction of the mind, and is therefore immaterial. Regarding knowledge, Idealists doubt the ability to know or understand anything existing outside of the mind. Though Idealism existed in one form or another in the days before Socrates, German philosophers like Kant, Hegel, and Schopenhauer popularized the idea that the mind projects reality throughout the 18th and 19th Centuries.
Idealism has been divided into two distinct categories, subjective and objective Idealism. In Subjective Idealism, reality exists as a conglomeration of the human subject’s senses. In Objective Idealism, proponents posit that an objective consciousness exists outside of the mind, though it is still immaterial.
Zeno of Citium founded Stoicism sometime in the 3rd Century BCE. Though tenants of the Stoic philosophy have persisted for generations, it is primarily associated with the teachings of a select few Hellenistic philosophers. In its most basic form, Stoicism is an area of study concerned with personal ethics and logic. According to Stoics, emotions function as an obstacle to happiness and thinking. In order to be both wise and happy, one must subdue emotions and live in the moment. This way, a person can experience misfortunes in life, but still remain happy. Stoics believed in a universal logic that brought order to nature. By practicing self-control and rejecting negative emotions, Stoics argued that a person could come to understand the natural order and logic of their existence.
Similar to Empiricism and a precursor to modern Analytic Philosophy, Positivism focuses on epistemological theories. Founded by French philosopher Auguste Comte in the early 19th Century, Positivism works as a philosophy of science, wherein the acquisition of knowledge relies on sensory observation, in conjunction with logic. This process of combining empirical evidence with logical analysis is now common place, but for centuries there was no formal movement promoting this process. While developing the school of Positivism, Comte also predicted and, to some degree, encouraged the introduction of social sciences. He saw society reflected in the fundamental principles observed in nature, and therefore believed that the structures of society could and even should be studied using science and reason. In this way, Positivism laid the foundation for future studies on human nature and society as a whole.
Structuralism is relatively modern as a philosophical movement, having begun in the early 20th Century. Claude Lévi-Strauss first coined the term, starting a movement that spread across much of Europe. At its core, Structuralism is a way of looking at humanity as part of a larger, ordered structure. For example, in the Structuralist view, an observer must understand an individual behavior in relation to other behaviors. Therefore, all behavior forms an abstract structure of universal laws. However, Structuralism is not just relegated to the study of behaviors. The basic tenants of the Structuralist philosophy have been applied to a wide range of disciplines. In this viewpoint, individual cultures, customs, behaviors, or qualities are meaningless when examined independently. Everything is interconnected in some way or another.
Phenomenology is a school of thought that began with Edmund Husserl in the early 20th Century. However, it is difficult to define Phenomenology from one author alone, as there are key differences among its various proponents. However, Phenomenology generally refers to the study of conscious experience, and the patterns that emerge among separate subjectivities. In essence, Phenomenologists attempt to take highly subjective processes (like consciousness and individual observations), and study it objectively. For example, a researcher in the school of Phenomenology may choose to observe the behaviors and thought processes of individuals, and make assertions about human nature based on the collected information. Contemporary philosophers have used the basic approach of Phenomenology to make advancements in sociological and anthropological studies.
Materialism asserts that all things in existence are the result of physical matter. Naturally, this school of thought stands in opposition to Idealism, which sees all of existence as immaterial. Where Idealism sees the mind as the center and, in a sense, the creator of all things, Materialism views the mind as a byproduct of natural, physical processes. In the Materialist view, the mind would not exist without a physical brain. Furthermore, Materialists believe that nothing would exist without matter as the foundational substance.
The concept of matter as the basis of all things is not new; it has been a popular idea in various parts of the world for centuries. The earliest and most notable adopters of this view were the Atomists in Ancient Greece, who argued that all of existence was comprised of indiscernible atoms. Nonetheless, scholars often credit Thomas Hobbes with formulating the Materialist view in his seminal work, Leviathan.
Existentialism began with Kierkegaard, who grounded his theories in individual human experience. Philosophers like Nietzsche and Sartre expanded on Kierkegaard’s arguments in favor of subjective meaning, believing that humans experience a sense of dread and confusion when faced with the absurdity of their own existence. This absurdity led Existentialists to conclude that existence is inherently devoid of meaning, and that meaning must be produced by the individual, for the individual. The phrase most often remembered from this movement is “existence precedes essence.” This famous quote from Jean-Paul Sartre’s influential lecture, Existentialism as a Humanism, perfectly summarizes the Existentialist viewpoint. This idea opposes the prevailing argument that nature provides meaning and order to life. Instead, according to the Existentialists, nature has no objective meaning, and therefore life can only be infused with subjective meaning.
Scepticism is an epistemological school of thought that, like its name implies, casts doubt on the certainty of knowledge. Scholars believe that Socrates was an early adopter of the Sceptical viewpoint. He used questions to bring himself closer to knowledge, but recognized that certain knowledge sat perpetually beyond his grasp. Scepticism as a concept is prevalent in almost every era of formal philosophy. This fact is self-evident, as most philosophical thought relies on the questioning of presuppositions.
However, historians attribute formal Scepticism to a handful of philosophers in Ancient Greece, including Socrates. Years later, Michel de Montaigne, Hobbes and Spinoza expanded on the early principles of the movement. Scepticism has evolved over time, and there are various subsets within the movement. Some Sceptics argue that only some things warrant Scepticism, while others take a more universal approach to the subject. However, the latter group often struggles to make valid arguments, as they must begin with the precept that they cannot know anything.
Cynicism began with a group of Ancient Greek philosophers known as the “Cynics,” sometime in the 4th Century BCE. The contemporary definition of Cynicism is far removed from the original tenants of the movement. Even the original Greek translation of the term, kynikos, had little to do with the school of thought itself. Originally, Cynics believed in living in accordance with nature, and rejecting human vices like wealth and power. According to the Cynics, virtue alone guarantees a path to happiness. Much like the Stoics, Cynics believed in maintaining a clear mind. They sought to be unburdened by the trivialities, contradictions, and falsehoods of the common man. Scholars generally agree that Antisthenes founded the movement. A student of Socrates, Antisthenes laid the groundwork for Cynicism, which emphasized an ascetic lifestyle, in which true proponents only sought the bare necessities for living, eschewing anything resembling luxury.
Philosophy has a long, complex history that is not simple to trace. Certain schools of thought emerged seemingly out of nowhere. Other movements resulted from centuries of debate and the reconfiguration of existing arguments. Some movements only existed in opposition to others, and some existed independently. So, when looking at the course of philosophy as a whole, one can see that the ebb and flow of ideas has been difficult to confine to one, unified timeline. Nonetheless, philosophy, from the days of Cynicism in Ancient Greece to the Existential movement of the 20th Century, has shaped the course of Western civilization.