[1] His breathing instruction and practices have also been recommended to augment meditation techniques,[2] to improve singing ability,[3] as a support for recovery from injury,[4] for stress reduction,[5] and for greater calm, presence, and clarity.
[6][7] In a 2004 critique of New Age literature by Jeremy Carrette and Richard King, he's cited as drawing upon the traditional Taoist interest in longevity but his writing is also categorized as an example of the "flattening out" of subtle cultural and philosophical religious ideas for the commercial and modern self-help and personal development movement.
[8] In the preface and introduction to The Tao of Natural Breathing, however, Lewis states that his intention in this book wasn't just to explore "the relationship of breathing to health and inner growth"[9] from the Taoist perspective, but also from his "observations and discoveries" from Advaita Vedanta, the Gurdjieff Work, Ilse Middendorf, Feldenkrais, and others, along with scientific principles from anatomy, neurochemistry, and physiology.
His techniques employ a mix of mindfulness and awareness practices, movements, postures, touch, and sound, with a stated emphasis on learning how to exhale fully and effortlessly.
He writes in his articles and books that when the exhalation is full and natural, the inhalation usually takes place spontaneously in the most appropriate way for the demands of the moment.
He describes those gatherings as helpful for seeing and going "beyond the boundaries of the conditioned mind--the habitual constellation of thoughts, emotions, sensations, beliefs, and judgments that each of us calls 'myself'."