There is, among a certain group of scientists, a shrill certitude about science which leads to overconfident proclamations on matters of philosophy (and by extension, religion). It is therefore refreshing to be reminded that many scientists have a different and more humble view. In this Scientific American interview with physicist George F.R. Ellis, he discusses Lawrence Krauss’ belief that physics has explained “why there is something rather than nothing.” Krauss’ metaphysical claim is, of course, much loved by New Atheists who believe that science has explained pretty much everything. Ellis, a giant in his field who co-authored The Large Scale Structure of Space-Time (1973) with Stephen Hawking, disagrees:
Krauss is presenting untested speculative theories of how things came into existence out of a pre-existing complex of entities, including variational principles, quantum field theory, specific symmetry groups, a bubbling vacuum, all the components of the standard model of particle physics, and so on. He does not explain in what way these entities could have pre-existed the coming into being of the universe, why they should have existed at all, or why they should have had the form they did. And he gives no experimental or observational process whereby we could test these vivid speculations of the supposed universe-generation mechanism. How indeed can you test what existed before the universe existed? You can’t.
Thus what he is presenting is not tested science. It’s a philosophical speculation, which he apparently believes is so compelling he does not have to give any specification of evidence that would confirm it is true. Well, you can’t get any evidence about what existed before space and time came into being. Above all he believes that these mathematically based speculations solve thousand year old philosophical conundrums, without seriously engaging those philosophical issues. The belief that all of reality can be fully comprehended in terms of physics and the equations of physics is a fantasy. As pointed out so well by Eddington in his Gifford lectures, they are partial and incomplete representations of physical, biological, psychological, and social reality.
And above all Krauss does not address why the laws of physics exist, why they have the form they have, or in what kind of manifestation they existed before the universe existed (which he must believe if he believes they brought the universe into existence). Who or what dreamt up symmetry principles, Lagrangians, specific symmetry groups, gauge theories, and so on? He does not begin to answer these questions.
It’s very ironic when he says philosophy is bunk and then himself engages in this kind of attempt at philosophy. It seems that science education should include some basic modules on Plato, Aristotle, Kant, Hume, and the other great philosophers, as well as writings of more recent philosophers such as Tim Maudlin and David Albert.
There are many unknowns and some things that may never be known. While some find this intolerable and feel a need to fill gaps with metaphysical assertions (which come in scientific and religious or mystical forms), I prefer the Lakota or wakan way, which strikes me as being methodologically scientific. By this understanding, some things will always be mysterious, paradoxical, inexplicable, and ambiguous. This should not bother us. Living with uncertainty is, in my estimation, far more invigorating than living with certitude.
At its best or in ideal methodological form, science is also about mystery, paradox, and uncertainty. This sense of science is beautifully expressed by physicist Carlo Rovelli in a recent piece for the New Republic:
Science is not about certainty. Science is about finding the most reliable way of thinking at the present level of knowledge. Science is extremely reliable; it’s not certain. In fact, not only is it not certain, but it’s the lack of certainty that grounds it. Scientific ideas are credible not because they are sure but because they’re the ones that have survived all the possible past critiques, and they’re the most credible because they were put on the table for everybody’s criticism.
The very expression “scientifically proven” is a contradiction in terms. There’s nothing that is scientifically proven. The core of science is the deep awareness that we have wrong ideas, we have prejudices. We have ingrained prejudices. In our conceptual structure for grasping reality, there might be something not appropriate, something we may have to revise to understand better. So at any moment we have a vision of reality that is effective, it’s good, it’s the best we have found so far. It’s the most credible we have found so far; it’s mostly correct. But, at the same time, it’s not taken as certain, and any element of it is a priori open for revision.
Hear, hear! Rovelli also has some interesting things to say about “naive” scientists who think that philosophy is superfluous. These scientists of course have a head full of philosophy, much of it metaphysical, but they don’t recognize it as such. Unexamined assumptions often work this way, and in other contexts we call this lack of awareness what it is: ignorance.