Sometimes things seem to happen for a reason. Some people call these events happy coincidences, others call them the work of God, or of many gods, while yet others see them as manifestations of one's karma.
I prefer the happy-coincidence choice, finding supernatural maneuvering a far-fetched hypothesis. In fact, the whole notion of a supernatural influence doesn't quite make sense, at least from a scientific perspective. After all, an "influence" denotes a physical occurrence or an event. And an occurrence is something that happens in the physical world through some kind of energy exchange. Any kind of energy exchange or force is very natural and requires a very natural cause. In other words, as soon as the supernatural becomes physical enough to be noticed or detected in some way, it can't remain supernatural anymore. A "supernatural influence" is an oxymoron. At most, it could mean something currently beyond our scientific understanding.
That said, there have been a few events in my life that defy logical explanation; or, at any rate, that defy any logical explanation that I can come up with. Although my position may sound somewhat shocking — especially coming from a scientist — to those who bet on our ability to explain everything, I'd argue that some things are unexplainable. In fact, I'll go further and argue that the unexplainable — to be distinguished from the not-yet-explained, which is the province of science — is unavoidable. And should be welcomed.
We are surrounded by mystery, by what we don't know and, more dramatically, by what we can't know. Hence my metaphor of the Island of Knowledge (which I elaborated in a recent book and briefly review here): If our accumulated knowledge of the world makes up an island, the island grows as we learn more. As with every island, this one is also surrounded by an ocean, in this case the ocean of the unknown. However — and here is the twist — as the island grows, so do the shores of our ignorance, the boundary between the known and the unknown. In other words, new knowledge generates new unknowns. Unless we stop asking questions about nature, there is no possible end to our search. Furthermore, scattered along the ocean of the unknown are regions of unknowables, questions beyond the reach of scientific inquiry.
Powerful as they are, our brains are limited, as are the tools of scientific inquiry, the machines we use to collect data about the world. Every measuring device has a range and a set precision. Telescopes can "see" only so far — that is, they can collect light from sources up to a certain distance or within a certain resolution limit. Whatever lies beyond their reach can't be seen, even if it's as real as what is seen. The same applies to microscopes, of course. Tiny things may escape detection, even if they are there, as real as the things we can see with the naked eye. If we continue into the world of subatomic particles, the smallest entities that exist, how far we can probe into the heart of matter depends on the machines we can build. Particle accelerators, such as the Large Hadron Collider at CERN, the European Organization for Nuclear Research, can probe matter only up to a certain limit. Whatever exists beyond that limit goes undetected. We may increase the accuracy of our machines and thus probe smaller distances, but we can't do this indefinitely, up to "zero" distance.
There is no perfectly accurate, all-seeing measurement. We are permanently myopic to some fraction of what exists.
Therefore, we must conclude that this ever-growing body of knowledge called science cannot explain all there is for the simple reason that we won't ever know all there is to explain. How could we possibly know all the questions to ask? To presume that we can know all there is to know only shows how supremely arrogant some people can be. It also flies against all that we have learned about how science generates knowledge.
Some may consider my task of exposing the limits of science to be dangerously defeatist, as if I were "feeding the enemy." But that is surely not the case. To understand the limitations of science is not the same as labeling it as weak or exposing it to the criticism of anti-science groups, such as Bible literalists. (See my post last week.) It is, in fact, liberating to those who consider it, as it frees science from the burden of being godlike, all-knowing and all-powerful. It protects its integrity in a time when so many claims from scientists get inflated beyond their validity, either by those making them (they should know better) or by the media. Cases in point include statements that we understand the physical mechanisms behind the Big Bang, which we do not, or that life is ubiquitous in the universe, which we know not.
Scientists should be quite careful about what they say and how they say it, as their pronouncements carry weight in the social sphere. Furthermore, and this is a key point for us, why should we want to know everything? Imagine how sad it would be if, one day, we arrived at the end of knowledge. With no more questions to ask, our creativity would be stifled, our fire within extinguished. That, to me, would be incomparably worse than embracing doubt as the unavoidable partner of a curious mind.
Science remains our most effective tool to explore the world in its myriad manifestations. However, we shouldn't lose sight of the fact that it is a human invention and that, as such, it does have limitations. Every system of knowledge is fallible. It needs to be in order to evolve. Failure compels change. Besides, we don't want reason to invade every corner of our existence. Some mysteries can be solved by reason, and others just can't.
Adapted from The Simple Beauty of the Unexpected: A Natural Philosopher's Quest for Trout and the Meaning of Everything (ForeEdge, June 2016).
Marcelo Gleiser is a theoretical physicist and cosmologist — and a professor of natural philosophy, physics and astronomy at Dartmouth College. He is the co-founder of 13.7, and an active promoter of science to the general public. His latest book is The Simple Beauty of the Unexpected: A Natural Philosopher's Quest for Trout and the Meaning of Everything. You can keep up with Marcelo on Facebook and Twitter: @mgleiser