Can We Trust Our Senses?

Can We Trust Our Senses?

Let me tell you a story.

I was twenty years old, and a junior in college. I was in one of Grove City’s required classes called Civilization and the Speculative Mind, a class about worldviews, philosophy, and Christian theology. I wrote my term paper for this class on why naturalism does not inevitably lead to nihilism. It was a response to the claims made by James W. Sire in the class textbook The Universe Next Door. He had made three “bridges” between naturalism and nihilism which I had set out to debunk. They were:

  1. Bridge One: “Necessity and Chance” (We came about by mere chance and therefore life is meaningless)
  2. Bridge Two: “The Great Cloud of Unknowing” (Our brains and “minds” are merely made of matter, which is indifferent to whether or not we correctly perceive anything, so we can’t be sure that any of our knowledge is accurate)
  3. Bridge Three: “Is and Ought” (Without a moral plumb line, naturalists do not have any significant way of knowing right from wrong)

A failed attempt

I had only ten pages to deconstruct all these ages-old philosophical arguments, and it was my first time trying to write anything in this genre. In the end, my final paper addressed only Bridge Three, because my arguments for the other two were too weak, and I just didn’t have the time to get to them all. My rebuttal to Bridge Two had always been my weakest. I really did not have an answer, and I was somewhat dumbfounded. Before it was scrapped entirely, the conclusion to my response to Bridge Two read:

While it seems nearly impossible to completely explain consciousness and the human mind from a naturalist standpoint, Daniel C. Dennett, one of Plantinga’s greatest ideological rivals, attempts, and arguably succeeds in, such a massive feat. In the beginning of his book Consciousness Explained, he voices his concerns with naturalist consciousness and the way that it may initially seem to lead to the nihilist lack of emotions or morals. However, throughout the rest of the work he shows that there are indeed several (very neuroscientific and biologically complex) ways to naturally explain consciousness with no “appeal to inexplicable or unknown forces, substances, or organic powers,” such as a deity.[1] Given that it is definitely possible to have conscious thought and ergo knowledge according to Dennett’s theories, the naturalist realm of thought and reflection is absolutely capable of staying just that—natural, sensible, and anything but nihilistic.

I really had no idea what I was talking about. And I obviously didn’t know yet that saying “Well, this person with a degree agrees with me, so I’m probably right” doesn’t count as an argument.

When I deleted two of the three sections of my essay, the single topic that stayed—morality—still pushed ten pages. As a previously apathetic college student, I was shocked at how much I wanted to keep writing this essay, but sadly, I knew that the other two topics would never get finished because I probably wouldn’t write without the motivation of a class. Well, six months later, I started writing The Closet Atheist Blog, the first iteration of the blog you’re reading right now. In many ways, I’m still writing the rest of this paper every week. And this week, I want to write my rebuttal to Bridge Two. Again.

Tim Keller’s bad logic

This came up as I was reading Tim Keller’s The Reason for God this week. He explained two related arguments (one for and one against God) and put them together, concluding that if you accept one, then you have to accept them both. Keller wrote,

Evolutionists say that if God makes sense to us, it is not because he is really there, it’s only because that belief helped us survive and so we are hardwired for it. However, if we can’t trust our belief-forming faculties to tell us the truth about God, why should we trust them to tell us the truth about anything, including evolutionary science?

Tim Keller, The Reason for God, p. 142

Honestly, I was blown away. I had heard the argument that we evolved to have religion because of agency detection and its survival advantage even if there is no god, and I had heard (and tried to write) about the circularity of trusting in your own senses even though there is no way to fully know that our senses evolved to be accurate, only to help us survive. But seeing the two arguments side by side really made me think. I remembered that years ago, I had had no answer to it, but I think I’m starting to get it now.

So, the question is: Can we trust our senses without God? If so, why? One of the reasons that this has always been hard for me to answer is because there are a lot of terms involved, and I, and probably others, tend to conflate them. There are our senses, perception, reason, consciousness, and more. I think consciousness is involved, but it’s not the central question I’ve been pondering all week. What I’m concerned with right now are perception (the data we gather with our senses) and reason (what we conclude those perceptions to actually be). Correct me if I’m wrong on these, but I will continue.

Later, Keller writes,

Though you have little reason to believe your rational faculties work, you go on using them. You have no basis for believing that nature will go on regularly, but you continue to use inductive reasoning and language. You have no good reason to trust your senses that love and beauty matter, but you keep on doing it.

Tim Keller, The Reason for God, p. 145-146

My response to this is: “Well, what do you want me to do? I have no choice but to trust my senses. It’s all I can do. They’re all I have.”

Is a pen a pen?

In my apologetics course three semesters after the aforementioned class, my professor challenged his students to give a reason why they believe that a pen is really a pen. His point was that we have faith in our own reasoning. I argued that we don’t need faith in this, because there’s not much more to being a pen than looking like one, writing like one, feeling like one, and in many cases, clicking like one. I don’t think we need faith that a pen is a pen, because it’s so easy to pick it up and test it out. (Read the full explanation here.)

I believe that this example roughly extends to all perception and reason. I think that we can trust our senses because they exist self-contained. If a pen looks, feels, and hell, tastes, like a pen, but in real reality, it’s a cat’s tail, how would we ever know? It seems like a pen to me, to you, and to everyone in the world who’s in their right mind. It doesn’t matter if it is really something else, because that doesn’t change what we all perceive it as.

So what if it’s not?

I’m no biologist, but I’ve heard that our retinas receive images upside down, and that images are flipped right-side up within the brain. Of course, oddities like this could be a reason to not trust our senses. But I say: if our brains didn’t flip our sight right-side up, what difference would it make? As long as we all see things the same way, who cares if everything’s actually upside-down? We can almost always trust our senses when we are in a normal, sober state of mind. If we can’t trust them, then we would know because sooner or later, it would conflict with what someone else is sensing. (I also think of colorblindness; I don’t see why it should be a problem as long as colors are internally consistent within your perception, and you can still communicate what you are seeing to others.)

We all know that too much alcohol can warp our perception. But in the case of a drunk person staring at the spinning ceiling, hoping not to puke, we know that that person can’t trust their senses, and so do they. It’s as simple as saying “Hey guys, uh, is the ceiling spinning to you?” “No, you’re the only one that sees the ceiling spinning, and you’re the only one that had ten shots.” And maybe there’s the off-chance that in the really real, the ceiling is actually spinning, and when we are drunk, that’s actually when our senses are correct.

But my argument is that even if that’s true, it doesn’t matter. We can verify that the ceiling is not spinning by getting on a ladder and touching it. If it’s really spinning, and we touch it and verify this, then we would have to be spinning, too. And if everything is spinning at the same rate as everything else, then we wouldn’t even know. I would never have found out that the entire planet was spinning if scientists hadn’t discovered it and told me so, because my whole experience has always been on the Earth, so I have no non-spinning experience to compare it to. To me, it just feels still. This is why it took humans so long to realize that the Earth rotates and orbits the Sun. It’s entirely counterintuitive.

God doesn’t answer the question, either

So maybe we didn’t evolve to be right. Maybe the only traits that we have are those that keep us alive. Our eyes are far worse than those of the mantis shrimp, and our ears are far worse than those of dogs. But we have no choice but to trust the senses we do have, with or without a sense-giving god. Probably the greatest flaw of Sire’s and Keller’s arguments are that the existence of a god wouldn’t even necessarily solve the problem of distrusting your senses.

If God knows what’s really real—if he knows that pens actually are cat tails and the ceiling really does spin like it seems to after ten shots—he sure hasn’t told us that. And after reading almost the entire Old Testament, I don’t think I would even trust the guy. It seems that the only source he can cite is himself.

Speaking of which, I read this page in preparation for this post. It gets into Plato’s Allegory of the Cave, which was on my mind, but I didn’t bring it up in case of getting something wrong.

[1] Dennett, Daniel. Consciousness Explained. (N.p.: Bay Back, 1992), Print.

0 thoughts on “Can We Trust Our Senses?

  • August 25, 2019 at 8:28 am

    “If a pen looks, feels, and hell, tastes, like a pen, but in real reality, it’s a cat’s tail, how would we ever know? It seems like a pen to me, to you, and to everyone in the world who’s in their right mind. It doesn’t matter if it is really something else, because that doesn’t change what we all perceive it as.”
    Yes, well said.
    Many of these issues amount to asking “Is it really real, as distinct from us thinking it is real?” But that’s an absurdity. Meaning comes from us. If we think it is real, then it is real enough. There aren’t two different versions of “real” — is it real to us or is it really real independent of us. Or, if there could be two versions of “real”, then the only one that matters is whether it is real to us.
    On the title question — “Can we trust our senses?”: We have no choice but to trust them, and trusting them has helped us make it this far through life. So we might as well keep trusting them.

  • August 25, 2019 at 8:29 am

    Ah, there is so much to respond to here! I will limit myself to two things. (1) Re “You have no basis for believing that nature will go on regularly, but you continue to use inductive reasoning and language.” Huh? No basis? How about my firm belief that the Sun would come up this morning? And it did! That the moon would rise and set monthly? Where did that belief come from? That water flows downhill? What is he talking about? No basis? Well, other than direct observation indicating a pattern that we can use, very, very accurately, with great success. Other than that, I guess.
    And (2) The eye indeed accepts images upside down and we make them right side up mentally. This ability was proven in an experiment in which a man wore goggles that inverted everything he saw. In just a few days he reported that everything looked right side up again (to the point he was able to fly a plane–he was a pilot). When he took the glasses off, another inversion took place that took a few days to rectify. But there is a lot more that is amazing about the eye. Apparently we see in color because of a poor mutation. Of the three color sensing cells we have in our retinas, one is clearly a distorted copy of one of the other two. The light it is sensitive to is just slightly different from the one it is a poor copy of, but that is enough for our brains to construct color from. (It seems we were originally “designed” to see in duotone, much like many other animals which do not see “color.”)
    Then, realize that all of the 3-D information coming to our eyes is discarded because the lens of the eye projects those images onto a 2-D surface (the retina). Consequently we have to reconstruct, mentally, all 3-D information that is of use to us (through clues like receding lines (for example railroad tracks). This is why there are so many optical illusions–they are all based upon our metal routines for reconstructing information that is discarded in the process of seeing. And, a recent discovery, of the information collected by the retinas, the vast majority of it is jettisoned when it is transmitted to the optical center of the brain, requiring even more reconstruction!
    All of this is necessitated by information processing limitations in our brains and is just now being sorted out. Oh, and along the way, no deity is necessary to explain anything. Those that claim one is needed are making a logical fallacy (since I do not understand this, then God must have done it isn’t good thinking).

  • August 25, 2019 at 10:01 am

    Have you ever seen James Rachel on moral autonomy—
“To continuously evaluate whether a being is good requires moral judgment, which requires moral autonomy.

Therefore it is not possible to continuously evaluate if a being is good while also worshipping it (or submitting to it)

Therefore, worshipping necessarily requires abandoning one’s moral responsibility, which is immoral”
    We have to trust ourselves. If we can’t do that how could we trust anyone else’s “selves” either?

  • August 25, 2019 at 12:10 pm

    According to David Eagleman, neuroscientist, we’ve evolved to sense a small portion of reality because we didn’t evolve to sense anything but this world and we’re really bad at that. Our senses only perceive a ten millionth of the light of the cosmos. We see a tiny tiny sliver of electromagnetic radiation. Just like there are cell phone signals (and other) passing through our bodies. Unless you have a cell phone you’d never know it.
    I guess I can trust the sense equipment (eyes, ears, nose etc) I have to get me through life, but know I’m missing out on most of the universe through no fault of my own.

  • August 25, 2019 at 7:50 pm

    Let me say that you are so kind to these people who write books, Rebekah. I enjoyed both of your explanations. I have two things regarding trusting senses. For me, it’s a no and yes and sometimes a maybe.
    First, while undergoing stressful (bad treatment, lack of sleep, and much more) military training I hallucinated. I saw a person who was not there. I really saw him. But I knew that I was hallucinating and why. It was like having a lucid dream, I knew reality but I was shocked that the image did not just go away.
    Second, since Steve mentioned a pilot. Pilots are trained (a lot) to trust their instruments over the senses they feel. For them, it is life or death deal. So, which senses do we trust? Flying by the seat of your pants can be deadly. They must trust some senses over others.
    I know you want atheists to behave civilly and be nice. However, I think people who use logic fallacies to support their claim should be called out for it for what it is: a fallacy is being kind, but often it is just a lie.

  • August 26, 2019 at 6:38 am

    I’m no biologist, but I’ve heard that our retinas receive images upside down, and that images are flipped right-side up within the brain.

    This only happens when we look at Australians – as everyone knows they walk upside down – and our eyes correct for this otherwise we’d all have massive migraines.
    Seriously, how cool was God when he thought of this?

  • August 26, 2019 at 9:40 am

    Just why should we trust one senses with god, if so why?
    I would say that whether god exists or not isn’t relevant to whether our senses can be trusted

  • August 26, 2019 at 10:16 am

    I realize that I didn’t quite address the fundamental question (“can we trust our sense?”) so … Yes, we can trust them to be exactly what they are, which is very, very limited. This is why scientists spend so much time inventing tools to extend and clarify our senses. What we want to sense and what we can sense are quire far apart. A philosophical/religious take on the question is clearly quite useless as we need to know a great deal about our senses and their limitations in order to come up with an answer to the question. Those speculations do not provide any of that information. Just thinking about “trust” and “senses” will get us nowhere we need to go.

  • August 26, 2019 at 1:56 pm

    I’ve been reading ‘Gunning for God’ by John Lennox over the last few days. He is a Christian Apologetist and in one of the early chapters of the book he throws out a few comments to the collected effect of ‘if there is not a rational cause to the universe, then why do we find that everything is almost designed to be investigated in a rational manner? If it is all by chance then how can we trust anything we discover or haved rationed out?’
    It’s a very interesting subject, I have no comments at this time – other than to say, Thanks! Keep writing and keep sharing your thoughts ✌️

    • August 27, 2019 at 10:45 am

      “‘if there is not a rational cause to the universe, then why do we find that everything is almost designed to be investigated in a rational manner?”
      After having studied the baffling field of quantum physics in college, I’m going to say that this assertion completely fails. There are many things in this universe which are not “designed” to be understood, at least not by us and our pathetic little monkey-brains. We evolved to understand the things in our environment, on our scale, at least well enough to survive. But for a lot of the things in the universe, we’ve had to design complex tools for measurement, and also tools for thinking (such as math) to be able to begin to untangle them. And some of the things we want to understand are still completely eluding us.
      (And then after nonsense assertions like that, they’ll usually turn around and assert that their god is immune to rational investigation.)

      • August 27, 2019 at 10:49 am

        Loved that! 🙌

    • August 27, 2019 at 1:51 pm

      To echo UD’s sentiment there is definitely some anthropocentrism in Lennox’s words there. It seems presume that we are a purposeful creation (evolution is not convergent, it did not try to produce it). It just turned out that natural selection favored the development of our intelligence in a particular region. Had there been some sort of prosperous predator constantly feeding on us, we might have turned out differently. So there is nothing even rational about us other than it is rational to think that our random evolutionary mutation of higher intelligence had advantages in the African savannas where we evolved. If human’s go extinct, should anybody put together a fossil history of the earth again, they might find, in the context of the entire history of life on Earth, that our higher intelligence might not have been all it was cracked up to be! 🙂
      I also feel like Lennox is (and likely purposefully) conflating rational and intentional. If someone throws a die and we record all the numbers, we can rationally investigate the phenomena to see if there is a pattern to what number shows up. A rational investigation will conclude that the number is random from 1-6 and we cannot predict with any accuracy other than having a 1 and 6 chance on being right on any throw What Lennox seems to be trying to smuggle in there is that the universe must be intentional. This is evidence by his use of the word designed. But more importantly when he says “designed for us” where he gives himself away in assuming we are the center of God’s creation.

      • August 27, 2019 at 2:02 pm

        Really like the dice metaphor here. Conflating rational and intentional seems to be a trick that Christian Apologetist use a lot…
        Thanks for writing that!

  • August 27, 2019 at 2:09 pm

    “Evolutionists say that if God makes sense to us, it is not because he is really there, it’s only because that belief helped us survive and so we are hardwired for it. However, if we can’t trust our belief-forming faculties to tell us the truth about God, why should we trust them to tell us the truth about anything, including evolutionary science?”
    The whole point of science is to free us from our biases. Much of it hinges on the repeatability of a result or the ability to use the results to make new hypotheses which will also be verified because the premises are true. If a pencil falls to the ground regardless about whether I’m sleepy, drunk, with caffeine, in Paris, under the ground, on a mountain, and falls to the ground according to many different observers, then it is clear that cognitive biases aren’t really impacting the results. And reliability matters a great deal. While our senses might be faulty, if we can use what we perceive to accurately make future predictions….”like the pencil always fell to the ground, this rock will also fall to the ground”. So an apologist might always make the argument that we still don’t know for sure, the reality is that this does not put all suppositions about what is real as equal. Some are simply more reliable than others. As you know evolutionary science is a well evidenced theory that is not only directly observable, but also allows us to make successful predictions. This does not put it on the same level as the notion of a divine consciousness, which allows us to make no predictions whatsoever.

  • August 28, 2019 at 9:05 am

    Sounds to me like Keller’s so far out of his depth he should give up now. Why? His arguments are based on unthinking, erroneous assumptions.
    God doesn’t make sense to us. We generally only accept the idea of god when we’ve been conditioned to. When we start to think for ourselves, and use our senses, rather than blindly accepting what we’ve been taught, then god makes very little sense at all.
    Has religion and belief has helped us to survive? I would suggest we would have survived perfectly well without it (and probably created fairer societies). At the very least, there’s no evidence to support Keller’s assumption.
    And as for being hard-wired to believe in god – what nonsense. We’re hard-wired to be inquisitive and to crave knowledge. In the absence of clues as to what life is and how the world works, we’re prepared to clutch at straws to try and sate that craving, like a man with a disease for which there is no cure being prepare to try the most ridiculous quack remedy.

  • September 16, 2019 at 9:15 am

    One theory is that god was invented by primitive man to explain away the (then) unexplainable events in his life. Fire, snow, thunder, eclipses, death, sickness. Man wasn’t sophisticated enough at that point to be able to understand gravity, or light , or even the track of the sun across the sky. So, he reasoned, it’s a the great sun god who gives us day, and the moon god who chases him out.
    Then it got complicated. Pretty soon anything unexplainable became a god’s wrath, or pleasure, or whathave you. Most convenient, although a lot of virgins were sacrificed in the process.
    Once men invented writing, someone wrote the stories down, and they became, not all that long ago, a narrative. People assumed that because it was written, it must be so, and God himself claimed to be the author.
    After all, would God lie?

  • September 16, 2019 at 9:20 am

    And we are, after all, all we have to work with. But as Bill likes to say, look both ways and mind the gaps.

  • September 16, 2019 at 10:32 pm

    We are all we have to go by, aren’t we. However, we do have each other to remind us that yes, that’s what mountains are, and up is up there and down is down there…We have those senses for a purpose (and not a divine one)–they are all survival mechanisms. It is a lot easier to distinguish a hungry lion against a forest background if you can see colors as well as shades of grey.
    you can hear as well as you do because your ancestors could, and it undoubtedly saved therir lives. Taste? Don’t eat that, it tastes funny. People without a sense of hot and cold frequently burn themselves.
    And not just humans. All animals have developed the senses necessary to help them suvive in their own way.
    So anyone debating whether senses are real or imaginary is probably about to find out how hot a stove REALLY is if you lean against it…


What do you think?