Snippets from Pinker on coherence

Snippets from Steven Pinker's The Sense of Style: The Thinking Person’s Guide to Writing in the 21st Century on coherence.

Pages 170 to 185 of Chapter 5 use a detailed examination of a page of John Keegan's 1993 magnum opus, A History of Warfare, to illustrate how an experienced and esteemed military historian failed to achieve coherence.

p171: The confusing opening of A History of Warfare provides us with an opportunity to look at three other contributions to coherence, which are conspicuous here by their absence: clear and plausible negation, a sense of proportion, and thematic consistency.

p172: More than three centuries ago, Baruch Spinoza pointed out that the human mind cannot suspend disbelief ...
The cognitive difference between believing that a proposition is true ... and believing that it is false ... has enormous implications for a writer.

p185: How could a seasoned author like John Keegan ... serve as a model of incoherent writing ...
... most of the problem comes from the very expertise that made Keegan so qualified to write his books.
... he became a victim of professional narcissism ...
... aftger a lifetime of scholarship he was so laden with erudition that his ideas came avalanching down faster than he could organize them.

A coherent text is a design object.
Like other designed objects, it comes about not by accident but by drafting a blueprint, attending to details, and maintaining a sense of harmony and balance.