Full House Read Free Page B

for all mammals), while the greatest successes of mammalian evolution—bats, rats, and antelopes— remain invisible.
    Let me not carp unfairly. If these pageantries only claimed to be illustrating the ancestry of our tiny human twig on life’s tree, then I would not complain, for I cannot quarrel unduly with such a parochial decision, stated up front. But these iconographic sequences always purport to be illustrating the history of life, not a tale of a twig. Consider the titles of the three series partly depicted in Figure 1: "The earth before the flood," "The parade of life through the ages," and "Prehistoric animals." An analogy might help in illustrating the oddity of such a pageant: Suppose that we wanted to stage a parade illustrating the growth of America’s coterminous forty-eight states through time. Would we let the float for New England ride only for the first mile, and then withdraw it permanently from view? Would we then add the Northwest Territories, the Louisiana Purchase, and the western lands in sequence, permitting only one float at a time by dismantling the preceding float after each new introduction? Would we be adequately showing the apotheosis of American expansion if the parade ended with a single float celebrating that little sliver of the southwest known as the Gadsden Purchase?
    Similarly, much as we may love ourselves, Homo sapiens is not representative, or symbolic, of life as a whole. We are not surrogates for arthropods (more than 80 percent of animal species), or exemplars of anything either particular or typical. We are the possessors of one extraordinary evolutionary invention called consciousness—the factor that permits us, rather than any other species, to ruminate about such matters (or, rather, cows ruminate and we cogitate). But how can this invention be viewed as the distillation of life’s primary thrust or direction when 80 percent of multicellularity (the phylum Arthropoda) enjoys such evolutionary success and displays no trend to neurological complexity through time—and when our own neural elaboration may just as well end up destroying us as sparking a move to any other state that we would choose to designate as "higher"?
    Why, then, do we continually portray this pitifully limited picture of one little stream in vertebrate life as a model for the whole multicellular pageant? Yet how many of us have ever looked at such a standard iconographic sequence and raised any question about its basic veracity? The usual iconography seems so right, so factual. I shall argue in this book that our unquestioning approbation of such a scheme provides our culture’s most prominent example of a more extensive fallacy in reasoning about trends—a focus on particulars or abstractions (often biased examples like the lineage of Homo sapiens), egregiously selected from a totality because we perceive these limited and uncharacteristic examples as moving somewhere—when we should be studying variation in the entire system (the "full house" of my title) and its changing pattern of spread through time. I will emphasize the set of trends that inspires our greatest interest—supposed improvements through time. And I shall illustrate an unconventional mode of interpretation that seems obvious once stated, but rarely enters our mental framework—trends properly viewed as results of expanding or contracting variation, rather than concrete entities moving in a definite direction. This book, in other words, treats the "spread of excellence," or trends to improvement best interpreted as expanding or contracting variation.

2
    Darwin Amidst the Spin Doctors
    Biting the Fourth Freudian Bullet
    I have often had occasion to quote Freud’s incisive, almost rueful, observation that all major revolutions in the history of science have as their common theme, amidst such diversity, the successive dethronement of human arrogance from one pillar after another of our previous cosmic assurance. Freud mentions three