Unknown, Unknowable and the All-knowing

I’m sure you’re familiar with the sobering, yet inspirational words of Carl Sagan about the simultaneous significance and insignificance of the pale blue dot we call home. I was somewhat surprised to see this excerpt from Pascal’s Pensées, in which he seems to be echoing a similar emotion from centuries ago.

Let man contemplate Nature in its entirety, high and majestic; let him expand his gaze from the lowly objects which surround him. Let him look on this blazing light, placed like an eternal lamp in order to light up the universe; let him see that this earth is but a point compared to the vast circle which this star describes and let him marvel at the fact that this vast orbit itself is merely a tiny point compared to the stars which roll through the firmament.

But if our gaze stops there, let the imagination pass beyond this point; it will grow tired of conceiving of things before nature tires of producing them. The entire visible world is only an imperceptible speck in the ample bosom of nature. No idea can come close to imagining it. We might inflate our concepts to the most unimaginable expanses: we only produce atoms in relation to the reality of things. Nature is an infinite sphere in which the center is everywhere, the circumference is nowhere. Finally, it is the greatest sensible mark of God’s omnipotence, that our imagination loses itself in that thought.

I highly recommend reading the rest of that excerpt here. Faced with the infinite vastness of the universe and the immensity of the unknown, Pascal is forced to draw the conclusion that it is also unknowable. This leads him to believe in God as the all-knowing painter of this majestic canvas. The eventual climax of this line of reasoning is Pascal’s Wager, which is his argument that a rational person must choose to believe in God and live accordingly, not necessarily because there is sufficient reason to believe in God, but because there is an infinity to be gained with that belief and nothing to be lost.

Leaving aside the wager, let us focus instead on the argument that the immensity of the unknown implies its unknowability. This might be the most common reason people place their faith in an omniscient being, particularly among those that do not believe in a personal God that intervenes in their favor in everyday life. There are a number of objections I would like to raise to this line of reasoning.

  1. Flawed premise: Our current understanding of cosmology and quantum physics suggests that the universe may not really be infinite in time or space. What is more, while we constantly find baffling surprises at the frontiers of our knowledge, that frontier is undoubtedly expanding. Today, we are more or less confident that we understand the underlying mechanisms for natural phenomena on vast scales stretching many orders of magnitude smaller and larger than us.
  2. Vastness does not imply unknowability: Equating the vastness of the universe to its unknowability betrays a lack of faith in
    • regularity- the fact that the laws of nature remain largely unchanged as we scale up or down in time and space
    • our power of observation- the fact that we can observe these scales today, despite not being endowed with the senses to do so directly
    • our power of reasoning- the fact that we can, through a process of induction and deduction, derive these regular laws and verify them

    Given our advances in the study of phenomena at these scales, many now believe that the frontier of the unknowable is, in fact, within us: our minds, consciousness, identity and emotions. While it may be a bigger challenge than understanding the cosmos, I am certain that we will, one day, look back at this belief as just as naive.

  3. Unknowability does not imply the existence of God: Even if we concede that the frontiers of our knowledge will forever remain bounded, engulfed in a sea of the unknowable, how does it follow that the universe must have an all-knowing creator? It is possible that there are laws that ultimately describe the working of the universe to sufficient detail, but which are unknowable to us because our own intelligence is somehow limited. We can postulate the existence of higher intelligences, say life forms on a distant planet that have, over the course of millennia of evolution, attained a level of intelligence that would be as alien to us as the ability to understand quantum physics is to a mountain goat.
  4. Uncertainty does not imply the existence of God: A possible counter-objection to my own objections above might be that our scientific laws are always uncertain, either by the very nature of our inductive process (there is always the possibility that we will discover phenomena that cannot be explained by our current understanding of these laws) or by the nature of the laws themselves (as quantum physics seems to have randomness inherent in it). While I believe this uncertainty is here to stay, this does not diminish our knowledge of the phenomena significantly: mathematics has allowed us to reason about uncertainty, measure it, bound it, and even make statements with virtual certainty in its presence. It is interesting that these capabilities were given to us by probability theory, the foundations of which were laid by, among others, Pascal himself! Once again, I am skeptical of the argument that this uncertainty leads us to believe in the existence of God. At the very least, we could argue that these laws allow us to claim that God must act only in a way that is statistically indistinguishable from pure chance.
  5. The question of existence of God may be ultimately irrelevant: We can view the advancing frontier of our knowledge as a receding frontier for the influence that supernatural phenomena can have on our lives. Newton’s theory of gravitation virtually guarantees us that if I drop a cup, it will fall to the earth, despite the existence or non-existence of God. The extent of that frontier does not leave much scope for intervention from God.

I’m not naive enough to think that any of the above will sway a faithful believer in the existence of God into submitting to skepticism. Maybe it raises some interesting questions that they must ask themselves about the reason for their belief. But it is possible that they would rather begin with the null hypothesis of the existence of God, transferring the burden to the skeptics to prove non-existence. Is there a more compelling principled objection to this line of reasoning than Occam’s razor?

Ultimately, our remarkable success in diminishing the unknown is a testament to what our mental faculties are capable of, and the immensity of the remainder of that project, our greatest source of inspiration.