Some narrow minded people may scratch their heads at how transhumanism can be spiritual. As a writer in spirituality, let me help elaborate. "[Dogma] cannot stand Spirituality. It cannot abide it. For Spirituality may bring you to a different conclusion than a particular [dogma]— and this no known religion can tolerate. [Dogma] encourages you to explore the thoughts of others and accept them as your own. Spirituality invites you to toss away the thoughts of others and come up with your own."― Neale Donald Walsch, The Complete Conversations with God

As I define spirituality, "it boils down to something very simple. Be the best person you can be, with progress, not perfection." That sounds like transhumanism to me. More of my thoughts on spirituality can be read here. https://medium.com/know-thyself-heal-thyself/spirituality-redefined-ff45cb53eaf2