The year 1745 wasn’t the best to be David Hume. This man, who many now consider to be the greatest philosopher to write in the English language, had over the years made enemies in the wrong places. In an epoch dominated by dogmatism, Hume was an outlier, and he wasn’t afraid to show it. And so, when he sought the chair of Ethics and Philosophy at the University of Edinburgh, people were outraged.

How can we possibly let a man who has undermined the will of God and religion in his writing teach about ethics, they wondered; a man who went out of his way to preach the wonders of extreme skepticism and cold atheism. As per their interpretation, this was a man who clearly sought to crush the foundation of morality on which they had built their society.

Now, these charges, of course, lacked merit, and Hume saw it to himself to correct them in an essay he wrote to the Lord Provost of Edinburgh titled A Letter from a Gentleman to his Friend in Edinburgh. He noted each charge and then wrote a rebuttal comparing it to his real position. Unfortunately, however, this didn’t help. The clergy was overwhelming against his appointment, which he eventually withdrew. He continued to be chastised for the rest of his life due to the content of his work.

As someone reading this in the 21st century, someone who is familiar with Hume’s work, I find this particularly interesting. Hume was a famous skeptic, no doubt, and he certainly did deliver some devastating critiques in regards to the existence of God and the religions built in his name, but the people’s core charges, it seems, suggest that he was a man entirely devoid of any kind of faith, that he was advocating some kind of nihilism — claims that couldn’t be further from the truth. In fact, as I see it, Hume’s later work, An Enquiry Concerning Human Understanding, is perhaps the most spiritual work of philosophy written in the Western world.

Today, the term spirituality has one of two connotations: the first is a classic religious one; the second is inspired by New Age culture. Both of them seem to diverge away from a world where science and reason dominate. Broadly speaking, I think it’s correct to suggest that both categories embody spirituality better than cold, hard reason and that they are right in doing so. Many smart and thoughtful religious people, for example, have a relationship with truth that most scientifically-minded people should be envious of. But at the same time, some of the most religious and New Age-oriented people I have ever encountered are also among the least spiritual people around. Why? Because spirituality goes beyond dogma—something Hume showed perhaps better than anybody.

Anyone who has spent enough time reading and thinking and living will come to the same conclusion that Hume did when he exercised his famous skepticism: In a world where we have complete information about everything, reason can give us certain answers; in the real world, however, where we are not even close to having all the answers — a world where words are fallible, where perception is fallible, where imagination is fallible, reason is more of a guide than it is a hallmark of truth. An example: Those who confidently claim that life is meaningless in the name of reason defeat themselves by doing so, because that claim can’t be made logically in a world we don’t fully understand — it’s an example of the intellect dumbing itself down with language when our experience so obviously tells us otherwise.

Now, by doubting everything from his opponents’ arguments and the promises of religion and even the principle of causality (an especially devastating critique that some philosophers believe we might never recover from) to even his own positions, Hume showed that we all mostly operate on faith and habit in ways that aren’t obvious. The point was never to illustrate that we can’t know anything, but more so, it was to humbly suggest that there are limitations to what the human mind can comprehend and understand, and we have to learn to operate in this complex world in spite of that fact without getting tangled away in our minds.

Maybe one-day scientific instruments will remove the limitations that hold us back, and that’s possible, but the chances are that the mysteries of both the Universe and our conscious experience are simply too complex to be confined to words and formulas. The confidence that many science-minded people (who often ironically don’t understand how science works, mistaking it for the dogma of scientism) have in science’s ability to comprehend and disprove what lies beyond the laws of physics are just as lacking in concrete evidence as the certainty of the narratives that some religious-minded people are intent on imposing on others.

In this vein, true spirituality is defined by skepticism — of both self and of authority, of both today’s religions and of today’s science. It’s individualistic, and thus, it’s the opposite of dogmatism. As soon as you use a phrase or a story to reduce away the complexity of life without acknowledgement, you are closing a gap left by reality with something that hides the uncertainty that is inherent in everything from our knowledge to our perception. True rationality is open-ended, and it’s skeptical about itself even as it does its best, knowing that an undiscovered mystery still lies ahead.

The hallmark of any dogma, whether religious or scientific, is the attempt to use today’s information to do away with the unknown-unknowns of a future without accepting that this future could very well prove us wrong, just as the past has been proven wrong, again and again, whenever we have entered a new paradigm. Today’s truths do indeed allow us to project the patterns we can expect to see tomorrow to a healthy degree, but this truth is always probabilistic, and even a high probability truth can be wrong in unanticipated ways due to our own fallibility.

Right now, the knowledge we use to assert the laws of physics is based on only 5 percent of the Universe, with the remaining 95 percent being clouded away by dark matter and dark energy — entities that we don’t have good assumptions about. Somehow, complex systems produce sums of wholes that are greater than their parts in ways that we don’t understand. We call this emergence, which makes it sound like we know something we definitely don’t, and it can be observed everywhere in nature. Gödel’s incompleteness theorems suggest that, due to the self-reference problem, logical systems will always be incomplete. And of course, again, Hume’s critique of causality gives us a reason to doubt the very foundation that we use to build all of our scientific knowledge on, and if not that (as the great Karl Popper almost convincingly argued), then it at least tells us that there might be knowledge out there that science can’t uncover in its current form.

When it comes to metaphysics, traditionally, philosophy has leaned towards either theism or materialism. The former reasons the existence of God and has usually monopolized spirituality, and the latter is concerned with the sub-atomic particles that it assumes makes up everything. This materialism is also the implicit assumption that guides most scientists and thus conditions people living in the modern era, which is mostly fine, except for one thing: Given where we are right now, materialism is just as much of a dogma as most materialists assume theism is. In fact, I’d argue that these categories are both wrong and that a rational skeptic practices science or religion as they do, in the relevant domain, but doesn’t make any confident claims about the future, thus embracing what I define as spirituality by default.

The question then, of course, is: What does this spirituality represent beyond skepticism? The answer is: A healthy respect for an uncertain reality; a mysterious future looked upon without assumptions and with only awe; a search for truth with open-ended rationality and a mind willing to entertain the absurd without pretending that the mask of language can define the unknown without the corroborating knowledge. Spirituality, in this sense, doesn’t rule out what reasonable people think of as God or the supernatural, nor does it ignore what science currently tells us; it lets you be you and me be me, as we both honor the uncertainty that reminds us that there is something bigger than us to be discovered.

Whenever I reflect on this spirituality in my own life, I am brought back to late-summer nights spent with people I love at an old German-style cottage in the country. Even driving away from the city, it would feel like we were being compelled by a force of nature to move away from the sounds, the lights, the people, to something more honest, more pure in its expression. We would drive until the highways were replaced by broken roads, the high-rise apartments by enveloping trees, the web of pressures and expectations in our lives by the openness of freedom and potentiality.

On these nights, as we settled in, as time began to dance to a different beat, we would sneak out of the back door and walk down to the dock and sit ourselves right where its wooden structure met the water. It would be quiet. The lake would be still. The moonlight would radiate. At first, the conversations that began inside would carry on outside, but eventually, our silence would match the silence of nature.

In this silence, we would stare. We would stare at the ripples in the lake, and we would stare at the movement of the forest beside us, but mostly, we stare up. We would stare at the unpolluted sky, at a million little dots of brightness, with each one of them representing a different center of reality, with each constellation telling a different story. And in these moments, I would be reminded of something I am otherwise quick to forget: I may be infinite in the complexity of my experience, but I am finite in the Universe. And with that, I would only smile — lightly, humbly, knowing that there’s more, knowing that this isn’t it.

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