Evolution is a theory of organic change, but it does not imply, as many people assume, that ceaseless flux is the irreducible state of nature and tha… - Stephen Jay Gould

In return for this great gift that I could not repay in a thousand lifetimes, at least I can promise that, although I have frequently advanced wrong, or even stupid, arguments (in the light of later discoveries), at least I have never been lazy, and have never betrayed your trust by cutting corners or relying on superficial secondary sources. I have always based these essays upon original works in their original languages (with only two exceptions, when Fracastoro's elegant Latin verse and Beringer's foppish Latin pseudocomplexities eluded my imperfect knowledge of this previously universal scientific tongue).

But, as we consider the totality of similarly broad and fundamental aspects of life, we cannot defend division by two as a natural principle of objective order. Indeed, the “stuff” of the universe often strikes our senses as complex and shaded continua, admittedly with faster and slower moments, and bigger and smaller steps, along the way. Nature does not dictate dualities, trinities, quarterings, or any “objective” basis for human taxonomies; most of our chosen schemes, and our designated numbers of categories, record human choices from a cornucopia of possibilities offered by natural variation from place to place, and permitted by the flexibility of our mental capacities. How many seasons (if we wish to divide by seasons at all) does a year contain? How many stages shall we recognize in a human life?

Progress in science, paradoxically by the layman’s criterion, often demands that we back away from cosmic questions of greatest scope (anyone with half a brain can formulate “big” questions in his armchair, so why heap kudos on such a pleasant and pedestrian activity). Great scientists have an instinct for the fruitful and doable, particularly for smaller that lead on and eventually transform the grand issues from speculation to action. While Lamarck (though a great empiricist on other questions) selected and armchair as the source for his evolutionary treatise, Darwin chose pigeons, and revolutionized human thinking. Great theories must sink a huge anchor in details.