How to Know Immaterial Things Exist

Author Greg Koukl Published on 03/06/2013

Can you prove religious, ethical, or moral kinds of things? Learn how to avoid a materialistic view of the universe.

If you’re Christian and you say, Yes, I believe there’s a Heaven and God, and there are souls and spirits, and right and wrong, but I don’t know it. I just have faith and hope that I'm right. Or if you hear others say something like, You can’t prove religious, ethical, moral kinds of things, these statements buy into a materialist view of the universe.

I had a conversation with a Christian couple who were getting challenges of these kinds from their non-Christian relatives who were saying, “We know things in science, but when it comes to everything else, it’s all fantasy.”

To help answer such objections, I walked them through a reflective exercise that I gleaned from the influence of J.P. Moreland. I had a pen, I placed it on the table, and asked them, “Is there a pen on this table?”

And they said, “Yes, there is.”

I said, “Are you reasonably confident that statement is true?”


“How do you know that?”

“I know it because I can see it there.”

In other words, you are trusting in the deliverances of your senses. You have no good reason to believe that your senses are misleading you, and so you are concluding that there is this object that we’re referring to that is sitting on this other object that we’re referring to—a pen on the table

There’s nothing mysterious about that, and I’m not skeptical about it. “I accept it,” is what I told them. I said, “Now I have another question. Do you know what you’re thinking about now?”

They said, “Yes.”

I said, “How do you know what it is you’re thinking?”

We were role-playing a little bit and he took the side of his brother-in-law, the secularist who had given him this challenge. He started describing brain chemistry as an explanation for how he knew his own thoughts.

I said, “Wait, wait, wait. That’s not what I’m talking about. I’m not talking about your brain chemistry; I’m talking about your thoughts.”

“Well, the thoughts are these electrical impulses that are going through my neurological...”

“Wait a minute,” I said. “I want you to think about what you’ve just said. You told me you knew what you’re thinking.”


“When you gaze, as it were, on the content of your mind so that you know what it is you are thinking, is the thing that you’re aware of neurons, brain tissue, and electrical impulses? No. The things you’re aware of are your own thoughts. Maybe there are electrical impulses that are happening when you’re thinking, and it may be that they’re always accompanied with the thoughts, but that isn’t how you know your own thoughts. You can just tell by reflecting, if you will, upon your thoughts themselves that you are not gazing upon something that has chemical properties. Thoughts have propositional qualities. They are not governed by the laws of physics, yet your brain chemistry is. They must be something different.”

Actually, I’m not trying to argue at this point for mind/body dualism, that your brain is different than your mind, though that seems to me obvious, just in this little analysis. I’m just simply asking about how we know something about our own thoughts. How does he know his own thoughts?

People have known the contents of their own minds from time immemorial without knowing anything about brains. The way we know the contents of our own thoughts is not by somebody else telling us, by some scientist taking a measurement, by using any of our five senses to apprehend it; rather, we have direct, unimpeded access to our own thoughts. We are directly aware. We simply introspect, and we know.

There is a faculty that we are using to know something important—that is, the contents of our own minds—and I’m not saying that we are always aware of everything that’s in our minds. We’re not.

I had a dream last night. I was watching the dream happen. I was the viewer, but who is it that scripted the dream? I scripted it, but I don’t know how I did it. From my conscious awareness, I was the viewer.

There are lots of things in our minds that we don’t know about. Still, at the same time, when we are beholding a particular thing in our mind we know it directly, and we know it incorrigibly. That means we know it without the possibility of being mistaken.

I continued the discussion with a series of questions. “Now, do you think you could be mistaken about the thoughts that you think you’re having right now?”

And both the husband and wife who were talking to me reflected, and then said no. They’re right. They can’t be mistaken. Could they be mistaken, though, about the pen on the table, which was the earlier discussion? And the answer they gave was yes, they could. In other words, it’s not likely that they are. There’s no good reason to be skeptical, but it is possible that they’re mistaken about that. However, it is not possible—and this seems obvious just on reflection—for us to be mistaken about the content of our own minds.

Here is the way this cashes out. I have really asked questions about two categories of things—material and immaterial things. We concluded that we knew things about both areas: the physical that we knew based on our senses (and this would be the way science tells us things) and immaterial things that we knew based on reflection.

We also realize that it’s possible to be mistaken about one, but it’s not possible to be mistaken about the other. Clearly we could be mistaken about virtually anything that we discover with our senses, even though we may not have good reason to believe so. So I’m not a skeptic in that regard. But it is not possible to be mistaken about the contents of our own mind and other kinds of immaterial, abstract objects that we’re aware of, like the laws of logic and reasoning and math, and a host of other things.

If that’s the case, then why are we saying things like, We can know things that science tells us, but we can’t really know about things that aren’t part of the physical world. It turns out that our confidence is just the opposite.

If you allow that to sink into your thinking, then it becomes a fruitful line of reasoning or questioning to ask what other things we might know with such confidence. Can we employ some of those same ways of knowing that we know immaterial things to other issues, like the existence of God or souls or morality? I think the answer to that is yes. There is no good reason to believe that we cannot have confident knowledge about facts of the immaterial world.

If we simply, by default, assert that we can’t know those things, then what Christians are doing is asserting a materialist worldview that is not only inconsistent with Christianity, but I think inconsistent with our basic perception of reality.

There are all kinds of things that we know that have little to do with the physical world, but we still know them. Friendship. Love. Loyalty. Goodness. Any moral virtue, any moral vice. None of these things are identical with behaviors or brain chemistry. The behaviors may signal that the virtue or the vice is present. You see behaviors from people around you that allow you to conclude that they are your friends, but the friendship is an immaterial thing. There are many things like this.

I’m trying to rock your world just a little bit epistemologically, in terms of the things that you know, to help you to see that the rejection of the idea of certitude about spiritual things is not well grounded.