Anthony Gottlieb, “The Dream of Reason.” Easiest to read.
Joseph Cotton, “Knowledge, Nature, and the Good.” Best on the Stoics.
Michael Ruse, “On Purpose.” Recently published, and relating specifically to evolution.
Julian Jaynes, “Origin of Consciousness in the Breakdown of the Bicameral Mind.”
As real reviews of Ancient World thinking I recommend the books listed above. What follows—my attempt to identify in the Ancient World the traditions leading up to the classic texts reviewed on this site—is my lay-person’s top-of-head gloss on the subject.
I’m inspired to undertake this by two thinkers. From Noam Chomsky I’ve come by the belief that we acquired language in two stages: first, we had to evolve a raw capacity for language, only then could individuals collaborate to construct actual languages. From Henri Bergson I’ve come to believe that whatever is distinctive about our thinking involved similar steps: first a capacity for it had to evolve in us, then that evolved capacity had to surface in consciousness, only after that, drawing on their awareness of that raw capacity, could individuals build the tools we actually think with. And since language appears to be the material those tools had to be created out of, particularly written language, much of the creation of those tools must have happened as recently as historical time.
Inadequate as my layman’s effort must be—I do urge you to read the books above—I feel impelled to round out this site’s reviews of “classic” texts on evolution with this introduction, a tracing back to their origins in evolved capabilities of the two main traditions I see leading up to and inspiring the writing of those texts. This itself I see as an integral part of the process of evolution, how these capacities evolved in us perhaps only a dozen or so centuries ago. Our conception of evolution would encompass both the evolution of species of living creatures and whatever we discover about the evolution of the contents of human consciousness.
Of these two traditions, one I see running through Plato, the Stoics and Christianity; it informed Enlightenment thinking about evolution as Deism, belief in a creative World Spirit. The other tradition I see originating in the paradoxes of Parmenides and Zeno, inspiring both Aristotle’s logic and atomism which in combination provided the foundations of modern science and today's "modern synthesis."
For these two evolved capabilities to be made into tools for thinking I’ve assumed they must first have surfaced in consciousness. Julian Jaynes has consciousness like ours arising around the beginning of the first millennium BC; he finds it missing in the Iliad but present in the Odyssey, he plots its emergence over the course of composition of the books of the Old Testament. A few centuries later the invention of alphabetic writing allows trains of thought to be transcribed as they would be spoken—whatever you could think you could record. A few further centuries later we have the axial period and the great flowering of philosophy in Greece.
Part of Henri Bergson’s genius was being able to intuit how the evolved capabilities behind these two traditions would have first registered in consciousness. One he thought had evolved in us as wisdom helping us deal with the living environment and apprehend our own nature; that he experienced as flashes of “intuition.” These consisted of intense illuminations about the nature of life, both his own, that of our species, and of evolution itself, his “élan vital.” In Plato this would emerge as a World Spirit, that the Stoics would re-name Zeus, a fifth element they thought suffused throughout the other four, responsible for maintaining order throughout the world, for the growth of living creatures and the creation of all novelty. This tradition Christianity first ransacked for whatever it needed to glorify its own god and then suppressed, only for it to resurface in the Enlightenment as the prime agent in Deism, the offices of a benign but distant god who created the world, including all living creatures, but who now declines to interfere in earthly affairs. Deism is the passion inspiring William Paley’s “Natural Theology,” his recital of the many wonders of the human body that no atheism, he assured us, could ever account for. The tradition continues in Robert Chamber’s “Vestiges of the Natural History of Creation,” a frankly Christian account of evolution, and Samuel Butler’s failed attempt, in “Life and Habit,” to rebut Darwin’s account of human origins, and finally in a flurry of thinkers early in the 20th century such as Whitehead and Bergson associated with terms such as “process” and “holism.” At this point it is once again suppressed, this time by the other tradition in evolutionary thinking, in which condition, damned as “vitalism” and “creationism,” it remains today.
Bergson saw the other tradition as having evolved in animals to equip them for mobility and action in the physical environment. It first registers in human consciousness as three dimensions of space by reference to which we could identify and learn to avoid physical objects, plus time, and reason. By reference to the dimension of time we could plot the order events came in. Through reason we could suppose that events connected somehow in those dimensions were caused by those happening nearby and coming earlier in time, and generalize from them to predict future events. Bergson’s inference is, we cannot assume this shows us reality, it may be no more than an illusion evolved in animals to help them to become mobile.
We can sense what early consciousness of time and space must have felt like through what was apparently common sense to the early Greeks. They seem to have experienced space and time as lumpy. The dimension of time, for example, consisted for them simply of a succession of events. I think we can tell this by how the paradoxes propounded by Parmenides and Zeno confounded their contemporaries. In these paradoxes time as experienced by intuition conflicts with time as measured by events. We know that an arrow aimed at a target will reach it quite quickly. But with time registered as successive events in which the arrow covers half the distance to the target, then half the remaining distance, and then half of that and so on, the arrow will never hit the target. That could have been a puzzle only if Greeks then had yet to construct even the most primitive tools for thinking about time. Pythagoras was celebrated for demonstrating that harmonious tones were produced by lengths of a vibrating string related by whole numbers. The discovery of non-whole number relationships in nature plunged his school into confusion. Again, this seems possible only if the dimensions of space too were experienced as lumpy.
The Greek’s response to these paradoxes was development of the second tradition, that includes Euclid’s geometry, Aristotle’s physics and logic, atomism, and skepticism. Suppressed at first it was gradually incorporated into Christianity, maturing into modern science until in the mid 19th century it supplants its host as our primary account of reality and sets out on its own. In Charles Darwin’s theory of natural selection characteristics serve as atoms by which individual humans vary, humans themselves serve as atoms in a process of selection for the fitness to survive and send progeny on to the next generation. Other notables in this tradition are Ronald Fisher, Richard Dawkins and, today, such physicalists as Sean Carroll.
Two figures participate in both traditions. One is Alfred Wallace, co-discover with Charles Darwin of natural selection who, a few years later, became convinced that such a mechanism could not account for the evolution of human capabilities, and began searching for the missing principle in spiritualism. The other is Charles’ grandfather, Erasmus Darwin, master of both traditions, called by some the last great thinker of the Enlightenment. In 1794 Erasmus published “Zoonomia,” the first modern-times account of evolution, a book of over 100 pages that, being bound together with an innovative 100-page classification of diseases, put all of Europe on notice that a major new account of human nature had to be taken into account. Erasmus started precisely where Aristotle left off, with male semen acting as the principal template for each new life, a belief reinforced I’m sure by microscope views of wriggling spermatozoa. ”Living filaments,” he called them, a remarkable prefiguring of what we think of as the genome. Could not all living creatures have over time come from such a filament, he wondered. At the same time, as a good Deist, he credits the World Spirit with providing the necessary initial impulse to life and maintaining order within it. He then goes on to outline in essence each theory of evolution that will be proposed in the following century, those of Lamarck, of Robert Chambers, and even of his grandson Charles. The course of evolutionary theory starts with its greatest and boldest thinker, from then on it all feels to me like anti-climax.
Where should evolutionary theory go from here? Bergson suggested one path. What the early Greeks did with their clumsy common-sense notions of lumpy dimensions of space and time, setting it on the path to becoming today’s science, we could do with what Bergson referred to as intuition. He clearly believed that the sources of wisdom available to us lie in capabilities already evolved in us, such as intuition, language and reason. There may be further wisdom latent in them. They may be the only sources available to an evolved creature like us.