When he says everything you can imagine is real, I suspect he meant just that: that literally any picture, song, work, outcome exists in your head.

You want flying cars? Think of one in your head. A trombone that plays dubstep style drops? Why not.

The minute you have an idea in your head, you can find details – the size of the windows on the flying car. The colors that the LEDs change to on the slide of the Dub-bone.