Artifacts of a Life Once Lived

The Question of Complexity Some are bold enough even to suggest sudden appearance of complex organisms. Stuart Kauffman explains in his book At Home in the Universe said, "I hope to persuade you that life is a natural property of complex chemical systems, that when the number of different kinds of molecules in a chemical soup passes a certain threshold, a self-sustaining network of reactions—an autocatalytic metabolism—will suddenly appear. Life emerged, I suggest, not simple, but complex and whole, and has remained complex and whole ever since… The secret of life, the wellspring of reproduction, is not to be found in the beauty of Watson-Crick pairing, but in the achievement of catalytic closure." (Quoted from http://biologicinstitute.org/2010/02/06/explaining-life-by-explaining-it-away/ Accessed April 19, 2010).This is not a scientific statement, but a metaphysical statement robed in scientific garb. How do we know that evolutionary explanations (there are various theories...