I think that the alternative to reasoned, rational, logical thought is mostly emotional thought. And emotions can make us act irrationally, illogically, and against reason. Anyone who has been head-over-heels in love with someone, or who has been in a blind rage over something that aggravated us sufficiently, knows how emotion can drive us to thoughts and actions that we would ordinarily consider foolish at best. This doesn't mean that we cannot react emotionally to something, or that it's always bad to do so. I cannot help but react emotionally to a view like Niagara Falls, for example. Or to an amazing work of art, such as a painting or a song. Emotion has its place, and helps us appreciate certain things in a way that logic and rationality cannot. But emotion shouldn't replace rational or logical thought in those areas where it best applies. To me, spirituality and religion is what happens when we try to stuff emotion into gaps that are best dealt with rationally and logically.
"Well, evolution is a theory. It is also a fact. And facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world's data. Theories are structures of ideas that explain and interpret facts. Facts don't go away when scientists debate rival theories to explain them. Einstein's theory of gravitation replaced Newton's in this century, but apples didn't suspend themselves in midair, pending the outcome. And humans evolved from ape- like ancestors whether they did so by Darwin's proposed mechanism or by some other yet to be discovered."
-Stephen Jay Gould
-Stephen Jay Gould