“From Bacon, Diderot learned that science need not bow down before a Bible-based view of the world; it should be based on induction and experimentation, and, ideally, used to further humankind’s mastery of nature. Locke delivered two related concepts. The first was a theory of mind that rejected the long-standing belief that humans were born with innate ideas (and, therefore, with an inborn understanding of the divine). In Locke’s view, the mind is a blank slate at birth, and our understanding of the exterior world comes about solely through sensation and reflection. This entirely nonspiritual view of cognition set up a second critical lesson. Since, according to the English philosopher, true knowledge is limited to what we can learn through our senses, anyone involved in seeking out nature’s secrets must rely on observation and experiment — on a so-called empirical approach — and avoid building huge systems based on fantasy.”