I suppose it depends on how you look at it, or perhaps on whether you're interested in how a bike works versus why a bike works. How is relatively easily answer

I suppose it depends on how you look at it, or perhaps on whether you're interested in how a bike works versus why a bike works. How is relatively easily answered; as the bike tilts it steers into the tilt, moving its base back under its center of gravity, in a way which damps itself thus getting back to upright without oscillating repeatedly or falling over. Why it works is the open question. We know that it's some combination of gyroscopic effects, rake, trail, and the different centers of gravity of the frame and fork, but we don't know the precise relationship between them that allows it to work.