We live in a time when a lot is expected from science. It seems that because science solves technological problems and improves technological abilities of society, we expect from it to answer to some more fundamental questions of human condition.
However, as Leszek Kolakowski points out in The Presence of Myth, next to the technological tree of human development, there is a parallel mythical and metaphysical three that is the crux of culture.
In his book The Soul of the Marionette: A Short Inquiry into Human Freedom, John Gray offers a wonderful passage explaining the limitations of science when dealing with the fundamental problems of human existence.
But science does not provide anything like a definitive picture of things. The practice of scientific investigation has gone with many different world-views. Among the scientists of the Renaissance, science and magic were closely allied. Unknown to themselves, some of the most militant twentieth-century scientific thinkers have adopted a view of things that is essentially Gnostic.
Nothing carries so much authority today as science, but there is actually no such thing as ‘the scientific world-view’. Science is a method of inquiry, not a view of the world. Knowledge is growing at accelerating speed; but no advance in science will tell us whether materialism is true or false, or whether humans possess free will. The belief that the world is composed of matter is metaphysical speculation, not a testable theory. Science may succeed in explaining events in terms of causes and effects. In some accounts it may be able to formulate laws of nature. But what does it mean for something to cause something else and what is a law of nature? These are questions for philosophy or religion, not for science.
While it may be the most effective means of explaining how the world works, science cannot explain its own achievements. Scientific inquiry may be successful because everything that exists obeys a few simple laws, which humans have begun to grasp. The order of the human mind may mirror that in the cosmos. Then again, the success of science may come from the fact that its practitioners inhabit a small corner of the universe that is not chaotic. Perhaps it is the disorder of the human mind that is more reflective of reality.
How we come to have the world-views we do is an interesting question. No doubt reason plays a part, but human needs for meaning and purpose are usually more important. At times personal taste may be what decides the issue. There is nothing to say that, when all the work of reason is done, only one view of the world will remain. There may be many that fit everything that can be known. In that case you might as well choose the view of the world you find most interesting or beautiful. Adopting a world-view is more like selecting a painting to furnish a room than testing a scientific theory. The test is how it fits with your life. How does the view that humans are machines fit with our life at the present time?
Over the past few centuries, many have asserted that science shows materialism to be true and concluded that any other view of things is an illusion that must be renounced. But this modern catechism is mistaken. Even if science could show the truth of materialism, it would not follow that every other view of the world must be rejected. Quite possibly the upshot of scientific inquiry will be that the human mind cannot function without myths and fantasies. In that case science would return us to our illusions.