Some of the greatest minds in science and the humanities have wondered — and attempted to answer — why the universe exists. That is, our universe, the universe, in the singular. But while it might be alluring to imagine what it would be like to live in a universe of ten dimensions, reality is at once simpler and more complex. From the wonderful MinutePhysics — who have previously explored whether the universe has a purpose, why the color pink doesn’t exist, how science education is stuck in the 19th century, why the past is different from the future, and why it’s dark at night — comes a lesson in science and semantics that distills the various hypotheses of parallel universes:

We must remember that physics is science, not philosophy, and in our attempts to explain the universe that we observe, we have to make claims that can in principle be tested — and then test them.

There is, however, plenty of room for philosophy in science — look no further than Jim Holt’s fantastic, mind-bending, and oddly soothing Why Does the World Exist?: An Existential Detective Story, one of the best philosophy books of 2012.