The quest about which Dewey writes is an ancient one, originating as a need for security from the perils of primitive life. This security was sought first, perhaps, by prayers and rites performed in an attitude proper to the holy or by magical manipulations of fortunate or lucky tangible objects. Mystery and glamour attended the former, while the latter were regarded as more amenable to practical control. Gradually this distinction was generalized and abstracted into that between the spiritual and intellectual and the material and practical; the distinction was also between superior and inferior respectively and resulted in an isolation of theory and knowledge from practice that has hampered human progress ever since.
Action is notoriously subject to failure or at least unforeseen results; material objects are only partially amenable to human control. Consequently, people were led to seek certainty in an eternal, immaterial realm of thought not subject to the risks of action. This was conceived as the realm of true Being or ultimate reality, unchanging, thoroughly rational, and governed by the laws of logic, and hence the only object of genuine science. The mundane world, on the contrary, was regarded as infected with nonbeing, unreality, and change; it was irrational and the object only of belief or opinion, not genuine knowledge. Moreover, the good was identified with the real so that value was attainable only by knowledge, and both were dissociated from action.
The developments of these distinctions have had ramifications in almost every traditional philosophical theory, Dewey argues. The ideals of certainty in knowledge, various metaphysical views, theories about mind and how it knows—even when formulated by strongly opposing schools—have stemmed from the jealously guarded barrier between theory and practice erected in the quest for certainty. Because modern philosophy has accepted the conclusions of natural science while retaining doctrines about mind, knowledge, and values formulated in prescientific ages, it has found itself increasingly isolated from the actual problems and values of contemporary life. Consequently, the basic problem for philosophy is the integration of beliefs about existence and those about values, especially since this gap has been widened by misinterpretations of certain developments of modern science.