An essential aspect of a painter’s canvas and a musical instrument is the immediacy with which the artist gets something there to react to. A canvas or sketchbook serves as an “external imagination”, where an artist can grow an idea from birth to maturity by continuously reacting to what’s in front of him.

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As a child, you probably had the experience of playing with a construction kit of some kind – Legos, or Erector Sets, or even just blocks. As a first act before starting to build, a child will often spread out all of the parts on the floor. This provides more than simply quick access. It allows the child to scan the available parts and get new ideas. A child building a Lego car might spot a wide flat piece, and decide to give the car wings.