During one of my AAPC lectures I read a portion of Richard Mitchell’s provocative little book The Underground Grammarian. Here’s the portion I read:
The mind is a rudderless wanderer blown here or there by any puff of breeze. If I mention watermelons, you must think of watermelons; if giraffes, giraffes. The very rare genus can keep his mind on course for a while, perhaps as long as a whole minute, but most of us are always at the mercy of every random suggestion of environment. We imagine that we sit down and think, but, in fact, we mostly gather wool, remembering this or that and fantasizing about the other. In our heads we recite some slogans and rehash the past, often repeatedly. Even in this foolish maundering, we are easily distracted by random thoughts, mostly about money or politics but often about sports or sex. Left to its own devises, the mind plays like a child in a well-stocked sandbox, toying idly with trinkets and baubles and often doing the same thing over and over again until some slightly more interesting game presents itself.
If we want to pursue extended logical thought, thought that can discover relationships and consequences and devise its own alternatives, we need a discipline imposed from outside of the mind itself. Writing is that discipline. It seems drastic, but we have to suspect that coherent, continuous thought is impossible for those who cannot construct coherent, continuous prose (pp. 39-40).
Without external stimuli and structure we are unable to think clearly and cogently.