Here is its logic: If there exists a source of psychological well-being that does not depend upon merely gratifying one’s desires, then it should be present even when all the usual sources of pleasure have been removed.
Waking Up: A Guide to Spirituality Without Religion
It is a 2014 book by Sam Harris. Harris discusses a wide range of topics including secular spirituality, the illusion of the self, psychedelics, and meditation. He attempts to show that a certain form of spirituality is integral to understanding the nature of the mind.