We tend to undervalue the importance of thinking and of books in one part of our cultural mind, even while we live among great libraries and universities.
One need only mention Newton or Darwin to make the point that ideas and books participate very deeply in reality—in Jamesian terms, they do indeed inform behavior—and therefore it seems fair to believe that James’s sufferings were as he described them and ended as he said they did, with his reading of Charles Renouvier.
The great ages in history, he says, "have said to the human being, ‘the inmost nature of the reality is congenial to which you possess.’" This may sound to us like an optimism the culture has outlived.
But he may only be describing an exceptionalism we dread to acknowledge.
It seems reasonable to speculate that these dark years moved James to immerse himself in the study of the new science of psychology and also to develop a philosophy that emphatically foregrounds the mind.
His experience of an idea as an entrapment may have moved him to develop his spacious, pluralist, open philosophy, which never subordinates the reports of consciousness to a system, and neither precludes new insight nor denies the authority of the context of individual consciousness that so largely determines issues of ambivalence or belief/disbelief.
(For James these latter form one category, one settled state of mind.) From our perspective, James’s account of his depression might itself seem questionable, since it does fall far outside the range of our understanding of such things, even calling up that ungenerous but respectable critical method rightly named suspicion.
To chalk it up to genetics or chemical imbalance or to lay it to the complexities of his childhood and family might seem more plausible to the general educated reader.
He is, however, entirely deserving of the reader’s trust.
James argues that emotion is not prior to its expression but identical with it, and that emotion can be limited by the decision to contain its expression.