All the basic technologies ever invented by human to feed and protect themselves depend on a relentless commitment to hard-nose empiricism: you cannot assume that your arrowheads will pierce the hide of a bison or that your raft will float just because the omens are propitious and you have been given supernatural reassurance that they will.

Bright-Sided: How the Relentless Promotion of Positive Thinking Has Undermined America (2009)