There was a debate recently between some philosophers and some physicists about whether or not philosophy was necessary anymore, give modern science. As you might expect, the physicists on the panel were anti-philosophy and their arguments were narrow, crude, and arrogant. And the philosophers, for their part, did an inadequate job of defending themselves. My answer to the question is this. People, including philosophers themselves, know what academic philosophers do, but they have forgotten what philosophers really do. They ask meaningful, intelligent questions. Physics is entirely dependent on philosophy--it is derived from philosophy and cannot exist without it. Without philosophy, science does not know what questions to ask. Every scientist who asks a fundamental question about any unknown aspect of nature is engaging in philosophy. As everyone knows, the word philosophy means the love of wisdom. That includes the love and pursuit of knowledge. Anyone who contemplates a phenomena of nature--the beauty of a flower, the stars in the sky, the course of a disease, or the behavior of an animal or person, and asks how or why it can be explained, becomes a philosopher.