How to summon our power to think elastically? First of all, play — and its cousin, daydreaming — can provide forums for the subconscious to form novel associations. (Think of Einstein’s delightful thought experiments — how he conceived the theory of relativity by imagining himself riding a beam of light.) Unfortunately, compulsively busy people regard activities like doodling and staring into space as a waste of time. And in this age of the ubiquitous pocket helper-brain, Mlodinow laments that the “dearth of idle time” fences off exciting new paths that the mind might otherwise wander. In this regard, Mlodinow asserts, people with ADHD may have a distinct advantage over others.