"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."