It's Friday morning, and maybe you're questioning your life a little: is it worth this long hard slog each week? But there are bigger questions to ask yourself, like, do you even exist in the first place?

This lovely video by James Zucker is really just a super-accessible take on René Descartes's Meditations on First Philosophy. That text itself is worth a read if you like that kind of thing, but for now, this video does a good job of probing some of life's biggest questions like, is this all just a dream ? Or someone's strange and intricate experiment? And how can we go about telling we are real, whatever that may mean? [TED Ed]