There are numerous varieties of skepticism as defined by the extent of the doubt. A relatively mild case might involve doubts about metaphysical claims. A truly rabid skeptic would doubt everything—perhaps even their own existence.
While many philosophers have attempted to defeat the dragon of skepticism, these attempts seem to have failed. This is hardly surprising—skepticism seems to be unbreakable. The arguments for this have an ancient pedigree and can be distilled to two simple arguments.
The first addresses the possibility of justifying a belief and thus attacks the standard view that knowledge requires a belief that is true and justified. If a standard of justification is presented, then there is the question of what justifies the standard. The same question can be raised into infinity and beyond. If no justification is offered, then there is no reason to accept the standard.
A second stock argument for skepticism is that any reasonable argument given in support of knowledge can be countered by an equally reasonable argument against knowledge. Some folks, such as Chisholm[i], have contended that we should assume we have knowledge and begin epistemology from that point. However, this seems to have all the merit of grabbing the first-place trophy without competing.
Like most philosophers, I tend to follow David Hume[ii] in my everyday life: my skepticism is nowhere to be seen when I am filling out my taxes, suffering through a committee meeting, or eating pizza. However, like a useless friend, skepticism shows up again when it is no longer needed. As such, it would be nice if skepticism could be defeated or a least rendered irrelevant.
John Locke[iii] took a rather interesting approach to skepticism. While, like Descartes, he seemed to want to find certainty, he settled for a practical approach to the matter. After acknowledging that our faculties cannot provide certainty, he asserted that what matters to us is the ability of our faculties to aid us in our preservation and wellbeing.
Jokingly, he challenges “the dreamer” to put his hand into a furnace—this would, he claims, wake him “to a certainty greater than he could wish.” More seriously, Locke contends that our concern is not with achieving epistemic certainty. Rather, what matters is our happiness and misery. While Locke can be accused of taking an easy out rather than engaging the skeptic in a battle of certainty or death, his approach is certainly appealing. Since I happened to think through this essay while running with an injured back, I will use that to illustrate my view on this matter.
When I set out to run, my back began hurting immediately. While I could not be certain that I had a body containing a spine and nerves, no amount of skeptical doubt could make the pain go away. In terms of the pain it did not matter whether I was a pained brain in a vat, being deceived by a demon, stuck in the matrix or really a pained brain in a runner on the road. In either scenario, I would be in pain and that is what mattered to me.
As I ran, it seemed I was covering distance in a three-dimensional world. Since I live in Florida (or what seems to be Florida) I was soon feeling quite warm and had that Florida feel. I could eventually feel my thirst and some fatigue. Once again, it did not seem to matter if this was real—whether I was really bathed in sweat or a brain bathed in some sort of nutrient fluid, the run was the same to me. As I ran, I took pains to avoid cars, trees and debris. While I did not know if they were real, I have experience what it is like to be hit by a car (or as if I was hit by a car) and experience involving falling (or the appearance of falling). In terms of navigating through my run, it did not matter at whether it was real. If I knew for sure that my run was really real for real that would not change the run. If I somehow knew it was all an illusion that I could never escape, I would still run for the sake of the experience of running. As such, while skepticism cannot be defeated, this simply does not matter to how one lives their life.
My view that skepticism does not matter might seem a bit odd. After all, when the hero (or victim) of a story or movie finds out that they are in a virtual reality what usually follows is disillusionment and despair. Intuitively, the idea is that it does matter whether the skeptic is right because if what I do is not real, it simply does not matter.
One way to support this view is to use the illustration of a dream: if I dream that I have won a gold medal in the Olympics, this means nothing—I have not really won the medal and it would be bizarre of me to brag to people about winning that medal in a dream. They would refute my prideful boasting with the obvious counter: you did not win for real.
As another illustration, imagine that I am on a run and see a baby being swept away in a flooded stream. I rush into the water and save the baby, only to find out that it is just a plastic doll. While I could be said to have acted bravely, if I claimed to have saved a child, I would be dismissed for the obvious reason that I had saved some plastic. Retrieving the plastic might make me an eco-hero, but it would not make me a hero—because the “baby” was not real.
The same would hold true in the case of skepticism in general: if my life is not real, everything I do is like that Olympic dream and all my “heroic” deeds are just like rescuing that piece of plastic. So, the skeptic must be defeated if life is to have any meaning. This, then shows that it does matter whether skepticism is right. While this objection is indeed formidable, there is a plausible reply and I now turn to it.
My view of what matters has been shaped by years of gaming—both tabletop (BattleTech, Dungeons & Dragons, Pathfinder, Call of Cthulhu, etc.) and video (Zork, Doom, Starcraft, Warcraft, Destiny, Halo, etc.). When I am pretending to be a paladin, the Master Chief, or a Guardian, I know I am doing something that is not really real for real. However, the game can be pleasant and enjoyable or unpleasant and awful. This enjoyment or suffering is just as real as enjoyment or suffering caused by what is supposed to be really real for real—though I believe it is but a game. Knowing that I am just playing games does not diminish the value of the experience, although I certainly concede that what I do in a game does not make me really heroic or really a winner in the “real” world.
If I somehow knew that I was trapped in an inescapable virtual reality, then I would simply keep playing the game—that is what I do. Plus, it would get boring (and probably awful) if I stopped playing. If I somehow knew that I was in the really real world for real, I would obviously just keep doing what I am doing.
Since I might be trapped in just such a virtual reality or I might not, the rational thing to do is keep playing as if it is really real for real. After all, that is the most sensible option in either case in this dilemma. As such, the reality or lack thereof of the world I think I occupy does not matter. As such, the skeptic need not be refuted in order for life to be meaningful. After all, gaming can be quite meaningful. The play, as they say, is the thing.
[i] http://philosophyfaculty.ucsd.edu/faculty/ewatkins/Phil107S13/Chisholm-Phil107.pdf
[ii] https://www.dascolihum.com/uploads/CH_12_Hume_Scepticism_in_Regard_to_the_Senses.pdf
[iii] https://www.iep.utm.edu/locke-kn/