The definition of philosophy is "The study of the fundamental nature of knowledge, reality, and existence." This can sound over broad and not be very satisfying, but it is a very good place to start a conversation. There are many technical philosophies that range from Absurdism to Zen and you can find them here. There is also the concept of philosophy as just a "general approach to a given topic". This is how most people that didn't study philosophy in school use the term. This one is a great conversation starter, because the direction taken by the person answering the question will give you alot of insight into their personality. They could spit out some word salad that doesn't mean much but is supposed to make you think they are smart, or they could just say I am a Zen Absurdist. Either way you will be glad you asked the question, even though actually, you didn't have to because The Well-Meaning Individuals of Freespeechland asked it for you. If you are interested in the philosophy I would recommend starting with this video .
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the government for a redress of grievances.