Hello, young scholars! Lately, I’ve been diving into Thomas Nagel’s “What Does it All Mean? A Very Short Introduction to Philosophy” (highly recommended, by the way!). This little book has reshaped some of my old arguments from my blog, “The Trouble with Certainty.”
Previously, I argued that we can’t be 100% certain of our reality because our perceptions and senses are incredibly flawed. However, I also suggested that direct observation, reasoning, and consensus could boost our certainty. Enter Nagel, who took my neat little arguments and shook them up like a snow globe.
Nagel starts with a simple question: Does the floor under your feet really exist? My immediate reaction was, “Of course it does, I can see it.” But Nagel says, hold on a minute. Your claim about the external world is based on the evidence of your senses, and you can only rely on that specific evidence about your visual experience only if you can already rely on the contents of your mind to tell you about the external world. In other words, you can only prove the reliability of your impressions by appealing to my impressions, going in a circular argument. It’s like trying to lift a bucket while standing in it.
Nagel compares this to a dream, where all experiences are self-contained. If I tried to prove that the floor underneath me existed, I would appeal to my own senses. However, in this case, my senses are wrong because the floor underneath me is part of a dream and in fact does not exist. So, my interpretations can be wrong.
Desperate for a way out of this maze, I thought about consensus. If everyone agrees on something, it must be real, right? Wrong again. Nagel introduces solipsism, the idea that only one’s own mind is certain to exist and that there is no real world. This implicates that all you see are your own impressions and products of your mind. However, this view is too radical for my liking. To think that I am the only one to exist in this world and that everything and everyone is just a product of my own mind is the stuff of nightmares.
Nagel offers a more palatable conclusion: skepticism. We can’t know anything beyond our experiences, and we can’t be sure if an external world exists. Even science, our beacon of truth, is based on perception. To truly know the world outside our minds, we’d have to prove our senses’ reliability, which we can’t do. It’s like trying to see your own eyes without a mirror.
This reminded me of Plato, the original skeptic. He believed in a world of true forms and argued that our ability to conceive them suggested their existence. Couldn’t this argument apply here? If we know there’s a reality beyond our grasp, we must be familiar with it somehow. Nagel explains this through verificationism: our views may be mistaken but can be corrected through further observation, like waking from a dream.
Yet, the skeptic argues that if reality is only what we can observe, then hallucinations—false observations—undermine this view. Once again, arguing against skepticism or solipsism leads to circular reasoning.
So, where does this leave us? If my reality is merely a product of my mind, why do I perceive the world in such a structured way? Why can’t I fly or reshape reality at will? This suggests the existence of a real, physical world. If my mind alone shaped reality, why would it impose such limits? But one could argue my mind is like a prison that imposes its own limits.
Now, let’s say the external world doesn’t exist. Nagel raises an important question: is it all right to continue believing in it? I say yes. Even if it’s an illusion, believing in an external world adds purpose and meaning to my existence. The alternative—a lonely existence where everything is a product of my mind—is too bleak to accept. For now, I’ll continue to hope that the world around me is real.
And there you have it! A rollercoaster ride through the world of philosophy with Thomas Nagel as my guide. Give his book a read. It might change how you see the world—or at least make you question if the floor under your feet is really there.