EVOLUTION AND RANGE

Spiritual traditions and practices promote a positive and lasting transformation of our experience of self and of the world. Such traditions and practices are ubiquitous in human societies, but it remains unclear why and how they developed. Existing theories on the nature of spirituality range from the suggestion that human minds are inherently predisposed to spirituality, to the idea that spirituality developed adaptively to offer moral guidance and to promote mutually beneficial, cooperative behaviors. Here, we assess this question from the perspective of biological and cultural evolution, and propose that spirituality developed as a cultural adaptation to a characteristic feature of human mental experience – the duality, or differentiation, of mental subject and mental object. This model traces the development of spirituality to evolutionary events at the core of human exceptionalism, and supports the transformational potential of spirituality in language consistent with scientific knowledge.‘Spirit’ shares the same root, ‘spir’ as respiration and refers to the animating force or soul which inhabits our material form and looks through our eyes, as if visiting from a special nonphysical ‘spiritual realm’ before ultimately returning to it. Before the theory of evolution, the idea of an immortal spirit animating our bodily form was a compelling explanation for our dualistic experience. Based on this view of mind–body dualism, spiritual practices that enforce subject-object duality by considering the body an obstacle to transcend were attempted – Christian monks flagellating themselves in the Middle Ages or practicing extreme fasting – but these practices largely failed to reliably produce transformed and happy human beings.