The book, by Bernard Roth, is utterly honest, remarkably so re: his emotional relationship with his wife. So it is moving with the touching guilelessness of a very very smart engineer, which the author is.
The human insights of the book only serve to show what exceptional investigators of the human condition men like Hume, Kant, Schopenhauer were. They went so much further than anything you see today in productivity porn books. And they said it all. But perhaps going that far is inimical to $.
So professional schools are forced to stop at some arbitrary $ point and say this is the human purpose of it all. Philosophers and mathematicians have no such restraint.