History and psychology indicate that people have inherent needs for stimulation and challenge, meaning and goals, social support, moral authority, explanation of existence, and the possibility of transcendence. Whether these needs result from physical evolution or intelligent design, they produce a concern about ultimate cause, meaning, and purpose for existence known as the "ontological imperative." Since understanding ultimate concerns is beyond physical science, elusive, and mysterious, people tend to attribute explanation to a metaphysical realm resulting in spirituality. Mountains symbolize obstacles in meeting the needs, and experiences in climbing mountains provide a vehicle both actually and figuratively for exploring associated mechanisms and impacts. Pursuit of the ontological imperative stimulates the attitude of spirituality that becomes conceptualized into personal religious systems forming beliefs that can be shared with others. Shared religions acquire dogma, structure, ritual, faith, and worship that then become institutional religions. As science develops, physical explanations supplant metaphysical explanations that many times conflict with religion. Faith in established belief competes with science producing a "great dilemma." A "great paradox" is that both are needed despite the conflict. The first chapter relates a personal experience climbing Mount Fuji that nearly ended in disaster, with the question of why people do such things. Chapter 2 is a brief summary of research supporting the human need of stimulation and challenge. Subsequent chapters alternate between mountain climbing experiences and brief summaries of research about why people continue to pursue difficult tasks, progressing from stimulation & challenge to goal accomplishment; emotions & awe; consciousness & cognition involving brain, mind, spirit, and soul; search for ultimate reality involving ontological imperative, spirituality, personal religion, and institutional religion; and finally to pragmatic reality involving science-religion dilemma and need-for-both paradox. This bottom-up approach leads to the final chapter's proposal for ameliorating conflict and dilemma caused by some religious beliefs: by accepting the great paradox and pursuing a seemingly unattainable goal; recognizing personal characteristics of spirituality exemplified in the five-factor model of personality; abopting an attitude of "nognosticism" whereby the limitations of present knowledge are acknowledged; and accepting "ecumenical humanism" whereby alternate beliefs are tolerated. Such an approach might be classified as "pragmatic pluralism." A basic theme is that for life to be meaningful and manageable, people need a sense of purpose and coherence that is best met by having a belief about the unknown and doubt of its validity. Contact author at wheelerrj@juno.com .