Are there Big Questions that don't have answers? Are some things simply beyond our capacity to understand with the finite lumps of gray matter in our heads? Are there "mysteries" in the world that simply can't be sorted out no matter how much gray matter is applied to the problem?
I think it is a mistake to try and weave tight arguments about some of the Big Questions from the tangled threads of our experience. Topics like God, free will, morality, evil, eternal life, the ultimate origin and fate of the universe, the purpose of life, the source of the order in the natural world, and so on simply do not open up to our investigations in any satisfactory way.
To see what I mean, compare the moral prohibition against murder to the scientific prohibition against violating the conservation of energy. The latter is easily studied and is a straightforward truth about our universe. It was, presumably, true even before our universe came into existence and it will remain true after our universe is gone. The morality of murder, however, is not so easily investigated. In fact, it seems impossible to say very much about morality, beyond certain utilitarian claims that, from the perspective of our species, certain behaviors are better than others. But does our failure to speak with clarity about something suggest that we are just whistling in the dark when we think about it all?
The challenges of speaking clearly about deep mysteries, however, are not arguments against their reality. We must not insist that our imperfect knowledge nets capture all truth. Sir Arthur Eddington, the astronomer who made the celebrated eclipse observations that confirmed Einstein's theory of general relativity, coined a helpful analogy in this regard. Imagine a fisherman, he said, catching fish every day in a net with three-inch openings in the weave. Every night he sorts his fish and sells them. After several years at his job the fisherman concludes that there are no fish in the ocean shorter than three inches. His conclusion is scientific in the sense that it is based on lots of careful observations. But he has failed to note the limitations of his net. Even if the ocean was filled with half-inch fish, he would never know because his net can't catch them.
Our knowledge quests, like the fisherman's net, are limited. The nets used by the physicist to understand matter do not capture the nature of life; the nets used by the biologist to understand the messy complexities of life in its manifold diversity, do not capture the underlying order the physicists have discovered. None of the nets employed by science capture morality and meaning.
How do we respond to the limitations of our nets? Do we conclude that there is no such thing as life because it doesn't show up in the nets of physicist? Obviously not. Do we conclude that there is no such thing as free will because it doesn't show up in any of the various scientific nets? Some leading scientists think so and there is quite an argument going on now.
"We don't have free will, at least not in the way everyone thinks we do. We are biologically determined creatures, with "biology" conceived broadly as "genes + environments + gene/environment interactions). Our brains -- and therefore our choices -- are as biologically determined as are our livers or kidneys. The appearance of choice is no more "real choice" than the "appearance" of a Western movie town, with its thin storefront facades buttressed from behind, is identical to a real town. Biological determinism is a fact ... "
Many scientists share this view. They reject as unreal anything that can't be caught in the scientific net. By these lights, nothing transcends science. Fish that cannot be caught in the scientific net do not exist. Free will, morality, and God cannot be caught in the scientific net so they must be fantasies conjured by naïve humans to meet psychological needs.
Such Spartan views of knowledge trouble me, despite my great appreciation for science. Human beings are finite creatures and it seems unreasonable to insist that no realities exist beyond those caught in our scientific nets. Or worse, to suppose that all realities must be such that their scientific descriptions are the only ones possible. Science constantly surprises us by pushing out its frontiers, and even rearranging what we thought was familiar.
But on what basis do we deny the possibility of realities that transcend science, rather than simply enlarge it? If, for example, there really are moral laws in the same sense that there are laws of physics, we will not discover that truth with science. I hasten to add that this is not an argument that a "religious way of knowing" will accomplish what science cannot. In the same way, it seems to me, physicists will never find the source of the order in their equations. It seems to me that physicists -- and this is my field -- have discovered that their work brings them to a boundary in their knowledge -- as opposed to a gap -- beyond which lies something quite extraordinary. Albert Einstein, in reflecting on the power of mathematical physics to describe the world, said "the most incomprehensible thing about the universe is that it is comprehensible." Paul Dirac spoke of the value of having "beauty" in one's equations. Another Nobel laureate physicist, Eugene Wigner, wrote a celebrated essay about how the great utility of mathematics in science was "unreasonable." Countless physicists have wondered about the uncanny ability of mathematics to accurately describe phenomena in nature. It remains a mystery and it is hard to imagine what developments could dispel this mystery.
Is it possible that free will represents another type of boundary to our knowledge? Between the determinism understood so clearly on one end of the spectrum, and the quantum indeterminism on the other -- neither of which can accommodate any meaningful concept of free will -- lies a theoretical no-man's land where those two incompatible aspects of our world overlap. I wonder if determinism and indeterminism represent two explanatory categories into which so much can be fit that we are too quick to assume that these categories are all-encompassing. And, since free will fits in neither category, there can be no such thing.