Reading David Mamet’s new book of essays, The Disenlightenment: Politics, Horror, and Entertainment , I was reminded of how loosely jointed and shape-shifting an essay can be. In this collection, a single essay can pivot from palindromes to springboks to why theatrical events always begin a few minutes after the hour. (Without fail, Mamet says, it takes six or seven minutes for the audience to become quiet with anticipation.) This same eight-page piece of writing then launches into an elaborate