Philosophy Definition: What the Word Really Covers

A philosophy definition in three senses

1. The subject. The discipline that uses argument and clear reasoning, rather than experiment or faith alone, to examine questions about reality, knowledge, mind, language, value and logic. You can study it at school or university.
2. A school of thought. A particular system of ideas held by a thinker or group, such as Stoic philosophy or existentialist philosophy. In this sense it can be plural: "Eastern and Western philosophies."
3. A personal approach. The beliefs or rules that guide how someone works or lives: a coaching philosophy, a design philosophy, a company's philosophy on remote work.

When people define philosophy casually, they usually mean the third sense. When a professor uses the word, she means the first.

The main branches in one table

There are also philosophies of science, mind, religion, language and mathematics, each asking what the basic ideas of that field really mean.

A lover of wisdom: the Greek root

The word reached English via Latin and Old French, starting from Greek philosophia, built from philo-, loving, and sophia, wisdom. A philosopher was literally a lover of wisdom. Ancient tradition credits an early Greek thinker with coining the term, but that story comes from later writers and is not certain.

For centuries the word covered almost all serious learning. Physics was once called natural philosophy, which is why the highest research degree in many subjects, including chemistry and economics, is still a Doctor of Philosophy.

Examples in everyday sentences

• She switched from law to philosophy in her second year because she loved arguing about ideas.
• The restaurant's philosophy is simple: local vegetables and a short menu.
• Our coach's philosophy is that defence wins matches.
• He took the bad news philosophically and started planning his next move.
• Ancient Indian, Chinese and Greek philosophy all wrestled with the nature of the self.

How philosophy differs from science and religion

Science answers questions by observing and testing; philosophy often works on questions that cannot be settled by an experiment, or on the assumptions science itself rests on, such as what counts as evidence. Religion usually begins from faith, revelation or sacred texts, while philosophy aims to accept only what can be supported by reasoning, even when it studies religious ideas. The borders are not sharp, and many thinkers have worked across all three. See also our page on science.

Using the word well

Common pairings: a philosophy of life, moral philosophy, a degree in philosophy, business philosophy, guiding philosophy, philosophy behind a decision. Say "the philosophy behind the policy" for the reasons that shaped it.

A small trap: calling every opinion a philosophy can sound grand. "My philosophy on parking" is fine as a joke; in a cover letter, "my approach to client work" may read better. And philosophical, as an adjective, has two faces: about philosophy ("a philosophical debate") or calm in the face of trouble ("she was philosophical about losing").

Questions philosophers still argue about

To see what the discipline actually does, look at a few questions that remain open: Do we have free will if every event has a cause? Is a promise binding when keeping it would cause harm? Is a person the same person over a whole lifetime? None has a single agreed answer, and that is normal. Philosophy is less about final answers than about making questions sharper and spotting weak reasoning, including your own. Related ideas include paradox, nihilism and wisdom, and plenty more thinking words are gathered under science and ideas.