Draw a bull.
Make it as realistic as possible.
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Easy enough?
Now draw a bull using only block shapes.
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Let’s take it further.
Abstract away all extraneous detail: draw a bull with only a few lines.
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Of course, Picasso was able to draw a realistic bull. He drew all of the above.
His magic though was in paring back—abstracting so that even a few lines can tell the same story.
Most folks are content with replicating the bull. Few explore the limit and produce something entirely new.