Born, went to school, played, traveled, went to more school, worked a bit, traveled even more, played some more, worked a bit more.
I dutifully maintain a pulse, heartbeat, and brainwave activity.
I seem to be stuck in a reality of only 3 obvious physical dimensions, a possible 4th dimension of time, a 5th one (according to Mr. Serling) or imagination, and a bunch of math dimensions, to make string theory workable. There may be others, but I have no way of proving this, conclusively. So I just go with it.