Lee Irwin develops a psychonoetic theory which prioritizes the soul and good mental health within spiritual development.

In this book, Irwin introduces a new theory of psychonoetic development, or “soul knowledge,” based in direct personal experience, encounters with the sacred, and the cultivation of positive virtues. This form of spiritual development reframes the embodied soul as a lived reality that each person must seek to develop through dialogue, self-analysis, and interpersonal relations. Unlike many similar practices, Irwin's psychonoetic theory purposefully accommodates any religious, agnostic, or atheistic orientation which fosters personal growth and mutual respect. In this sense, this book offers a post-traditionalist framework for soul development open to a wide variety of worldviews and possible alternative metaphysical perspectives. Through this broad focus, psychonoetic theory integrates an awareness of paranormal perceptions and afterlife possibilities, altered states of consciousness, mystical encounters, and transformative spiritual experiences. At its core, Irwin's approach to psychonoetic theory supports the value and import of transpersonal encounters as central to spiritual life distinct from any religious orientation, prioritizing the importance of cultivating personal integration, positive psychology, and openness to dreams and spiritual intuitions.