Prior to the Enlightenment, the stories we told about nature and ourselves were teleological. Existence had purpose. And this wasn't just the case in the realm of religion. Pre-Enlightenment science was teleological. The world moved and changed as the objects and creatures in the world sought their proper goals and ends. As Aristotle taught in his physics that governed the Western world, the best way to understand why things are the way they are is to understand what purpose they were designed to serve.
This teleological gaze was killed off by the Enlightenment and the rise of modern science. You could argue that this teleological-to-causal shift was the fundamental change that gave rise to the modern world, and represents the critical imaginative difference between "science" and "religion."
Darwinian evolution is Exhibit A of the teleological-to-causal shift. According to a teleological account of biological life, the various evidences of "design" we found in nature pointed toward purposes, toward a telos. This "fit" between design and purpose was evidence of a divine intelligence or rationality (logos).
But where teleology looked forward toward a telos--a goal, reason, end, or
purpose--the story Darwin told looked backwards at antecedent causes. Darwin pointed out that "design" could be produced through dumb and random processes. Genetic variation coupled with natural selection ("survival of the fittest") could mold phenotypes over time, fitting them to ecosystems and thereby creating the illusion of "design." Under the teleological gaze, cats have claws so they can catch mice and humans have opposable thumbs so we can make tools. But after Darwin, these teleological accounts were rejected. No purpose or telos drove the evolution of claws or thumbs. These arose through random genetic variation and the culling of natural selection.
Obviously, a causal approach to the natural world has yielded great fruits. Our capacity to manipulate the causal fabric of the world has given us enormous technological power. But the demise of the teleological hasn't come without a price. Specifically, we've traded meaning for manipulation.
The causal gaze gives us the ability to manipulate the physical universe, but at the cost of meaning. The causal gaze strips existence of purpose. Again, Darwin is a good illustration here. Why do we exist? Because of dumb, random physical processes. There's no "reason" behind our existence beyond luck, and we might just as well have not existed. In short, the causal gaze gives us great technological power but its pricetag is nihilism. We have material mastery but spiritual incompetence.
As the atheist and Noble Prize-winning physicist Steven Weinberg summed up, "The more the universe seems comprehensible, the more it also seems pointless."
