It is not different with the optical perceptions.

The best does not come from without.
Of all internal functions which create the meaning of the world around us, the most central is the attention.

The chaos of the surrounding impressions is organized into a real cosmos of experience by our selection of that which is significant and of consequence.

This is true for life and stage alike.

Our attention must be drawn now here, now there, if we want to bind together that which is scattered in the space before us.