Philosophy is basically hard to define but you can recognise it when you see it.

Philosophy is the study of general and fundamental problems, such as those connected with existence, knowledge, values, reason, mind, and language. It is distinguished from other ways of addressing such problems by its critical, generally systematic approach and its reliance on rational argument. The word "philosophy" comes from the Greek φιλοσοφία (philosophia), which literally means "love of wisdom".

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1. Love and pursuit of wisdom by intellectual means and moral self-discipline. 2. Investigation of the nature, causes, or principles of reality, knowledge, or values, based on logical reasoning rather than empirical methods. 3. A system of thought based on or involving such inquiry: the philosophy of Hume. 4. The critical analysis of fundamental assumptions or beliefs. 5. The disciplines presented in university curriculums of science and the liberal arts, except medicine, law, and theology. 6. The discipline comprising logic, ethics, aesthetics, metaphysics, and epistemology. 7. A set of ideas or beliefs relating to a particular field or activity; an underlying theory: an original philosophy of advertising. 8. A system of values by which one lives: has an unusual philosophy of life [1]

Basically philosophy is about finding things out by reason, Science deals more with thorough empirical investigation.