I Think, Therefore I Know

introspection, evidence

In graduate school, I once took a course on mind-reading. Seriously. But it was a big disappointment. It turns out that what academics mean by ‘mind reading’ is just reading people’s body language. Next time I’ll make sure the course is taught by Professor Xavier of X-Men fame. We are all glad, though, that actual mind-reading (mental telepathy) is currently impossible for humans (as far as we know). I would not want people knowing my inner-most thoughts, nor would I want to know the secret thinkings of others. We enjoy the safety of being able to hide a part of ourselves, only revealing it to those we deem trustworthy. But this means that there is a huge body of knowledge that I alone have access to: my own thoughts! This access comes through something called introspection.

Introspection allows us to access our memories and be aware of the logical progression of our thoughts. It enables us to consider the sensations created by the five senses. Introspection is how we know our reaction to a person’s story–whether we believe it or not, whether it makes us angry or sad. It ties everything together and makes knowledge possible. Philosophers and scientists puzzle over the nature of introspection, but all recognize it’s importance.

Introspection and Faith

religious experience, prayer, evidence, introspection

In other posts, I’ve discussed various kinds of evidence for belief in God. But how can introspection provide evidence? In Christian theism, we believe that God reveals himself, among other means, through a special form of internal communication or awareness. Some, like John Calvin, have called this the “sensus divinitatis.” God, through the presence of the Holy Spirit within us, can “speak”to us, lead us, comfort us, etc. The apostle Paul, in his letter to the Roman church, says that believers are “led by the Spirit of God.” It is the Spirit who “testifies with our spirit that we are children of God.” (8:16) Jesus himself taught that when the Spirit comes to dwell in us, He will “teach you” and “remind you of all the things I told you.” (John 14:26).

This means that we have access to evidence that comes directly into our minds from God, and we access this evidence via introspection. This probably works in the same way as when you suddenly have a new idea, and you reflect on it. But in this case, it is God who forms the idea in your mind, rather than your own cognitive processes. (So mental telepathy IS possible! But only between you and God.) So a Christian may be able to know that God exists and loves her simply by introspecting on evidence conveyed to her internally by the Spirit.

This Sounds Crazy

If you consider yourself a skeptic of Christianity, then this might sound crazy. But this is where you have to distinguish between irrationality and falsehood. Because if there is a God, then there’s no obvious reason why God couldn’t speak to humans in the way I’ve described. The Christian may be factually wrong, but she isn’t being irrational or crazy. To make a “crazy” charge stick, the atheist must show that there is no God, which cannot be done.

Still, I admit it is odd to say, “I know there’s a God because of this voice in my head.” (Though, it isn’t literally a voice.) We would never accept such an argument for any other claim, right? “I know there are aliens/will be an earthquake/Bob is the murderer because of this voice in my head.” So what makes the God case special? 

Here’s one way to think of it. If Bob were the murderer, there’s no reason to expect that I could know this via a “voice” in my head. But if the Christian God did exist, we have good reason to expect that a Christian could know this via a “voice” in her head. In other words, the Christian God (if real) is willing and able to communicate with believers in this way. Admittedly, the case of aliens is more plausible than the murder case. But we still lack good (non-ad hoc) reasons to think aliens would communicate with us in this way. It’s also important to point out that this is not necessarily the way that people initially come to know that God exists. This source of evidence comes into play only after a person comes to believe in the Christian God.

Craig’s Folly?

William Lane Craig has infamously/famously (depending on your viewpoint) said that “the fundamental way in which we know that Christianity is true, including the belief that Jesus rose from the dead, is through the self-authenticating witness of the Holy Spirit.” He goes further to say that the inner witness of the Spirit “can be so powerfully warranted in our lives that it will intrinsically defeat the extrinsic defeaters that the atheists and skeptics bring against it.” In English, what this means is that no matter what evidence is presented to him against Christianity, the inner witness of the Spirit will override all of it. Is this reasonable?

Critics of Christianity go berserk at this point. This sounds like flat-out irrational, blind faith to them. Surely, they reason, there could be evidence that would be sufficient to cause a reasonable person to give up their belief in Christianity. But while I may not necessarily agree with Craig, I think the open-mouthed astonishment at so audacious a claim rests on a misunderstanding. 

Clarifying Craig

The fact is, there are certain beliefs we all hold that are so fundamental to us, no amount of counter-evidence would ever be enough to uproot them. Consider this example from atheist philosopher, William Rowe: 

“Suppose your friends see you off on a flight to Hawaii. Hours after the take-off they learn that your plane has gone down at sea. After a twenty-four hour search, no survivors have been found. Under these circumstances they are rationally justified in believing that you have perished. But it is hardly rational for you to believe this, as you bob up and down in your life vest, wondering why the search planes have failed to spot you.”1

In truth, no matter how much evidence they produce supporting your death, it wouldn’t be enough to convince you. So the idea of a powerfully warranted belief that is immune to counter-evidence is a perfectly coherent notion, common to everyone. And Craig simply argues that the inner witness of the Spirit is just such an indefeasible source of evidence.

Conclusion

So no matter your religious views, there’s no harm in acknowledging the reality of introspective evidence. Such evidence pervades our beliefs–it is indispensable. And even the religious skeptic can concede the following conditional claim: If the Christian God exists, then Christians have introspective evidence of his existence. (In fact, the only way to refute such a claim is to show that God exists, but no such introspective evidence exists!) Still, skeptics can maintain that given atheism, no such non-misleading evidence actually exists! In any case, everyone benefits from reflecting on the role of introspective evidence in their belief system. 

Is There Evidence for God?

skeptic, evidence

Summer, 1998. I traveled to Europe (Hungary, to be precise) and sat down in a little restaurant one day for a bite. I ordered the “Greek salad.” I love Greek salad! I’ve eaten many Greek salads growing up in Florida: shredded lettuce with cucumber slices, beets, feta and shrimp. To my horror, what emerged from the kitchen was a bowl full of chopped cucumber and tomato, with feta, onion and Kalamata olives. No lettuce at all! This was most definitely not a Greek salad.

Greek salad, evidence

But I was wrong! 20 years later, I found myself in Athens, Greece. To my surprise, I discovered that my salad in Hungary was authentic. Succulent chunks of cucumber and tomato, mixed with onion, feta and olives. It turned out that I needed to adjust my definition of ‘Greek salad.’

I often hear skeptics say things like, “there’s no evidence for God.” But I think this view arises from some confusion about what evidence is. The search for evidence resembles my blunder with Greek salad. When we look for evidence, most of us don’t know what we’re looking for. We follow a mistaken notion of evidence, and finding none, we proclaim its absence. So what is evidence, exactly?

What Is Evidence?

smoke, evidence

“Smoke is evidence of fire.”1  I think this makes sense to most of us. When we say this, I think we mean something like this: “Well, fire causes smoke, and I’ve always seen smoke with fire, so I think it’s pretty likely that we’ll find fire where that smoke is.” The reason this kind of logic works is because evidence raises the (epistemic) probability of what it supports (e.g., a hypothesis). In this case, the presence of smoke raises the probability that there is a fire. Does it guarantee the presence of fire? No. It is possible to have smoke without fire. But nevertheless, when we see smoke, we are quite rational in thinking, “there’s a fire over there.” So evidence is something that raises the probability that a hypothesis is true.

Kinds of Evidence

What are these “somethings?” Evidence comes in a variety of kinds. Philosophers typically recognize five sources: perception, testimony, memory, inference, and introspection. The smoke example is a combination of perception (seeing the smoke) and inference (making a logical or causal connection between smoke and fire). Many of our beliefs rest almost solely on the support of evidence from our five senses, like my belief that the coffee I’m drinking is hot. Others, like mathematical and geometrical beliefs, are backed up by pure reason.

restaurant, evidence

Another illustration: The other day, I thought I remembered visiting a certain restaurant with my kids. But one of my kids said he’d never been there. So, I asked two of my other kids, and they both agreed with kid #1. So, what do I do? I have conflicting evidence. My memory of visiting the restaurant raises the probability that we went there, but the testimony of three other people lowers the probability! My total evidence suggests that it is unlikely that I took my kids to the restaurant. 

Introspection comes into play when we think about the contents of our own mind, or of various bodily states. When I feel a sensation of pain, or have a feeling of sadness, that evidence makes it 100% likely that I am in pain or sad. If someone were to tell me, “You’re not in pain,” my introspective evidence would override them. I have special, private access to the states of my own body and mind.

All of these come to us via some kind of experience. Perceptual experiences (hearing, seeing, etc.), introspective experiences (self-awareness), inferential (cognitive) experiences, and perhaps religious experiences. And all of these are subject to error, so some caution (but not paranoia) is important. The rule of thumb is: trust your faculties unless you have clear reason to doubt them, e.g., you just took an hallucinogenic drug.

Evidence and God

court room, testimony

So how does all this apply to God? Well, our evidence for God can come in all five of these forms. I can hear or read testimony from someone else who has experienced God in some way. It’s like court testimony. I’ve served on one jury, and the jury’s eventual belief in the defendant’s guilt was based largely on the word of several witnesses, including the victim. Hearing a credible witness testify that “X happened” raises the (epistemic) probability that X happened. It works the same way with testimony about God (including written sources, like the Bible).

I can infer from various experiences of my own (“religious experiences,” perception of order and design in the universe, etc.), or from other facts (everything that begins to exist must have a cause) that God exists. The logic of the Kalam Cosmological argument or the Fine-tuning argument raise the probability that God exists. Religious experiences, when the best available explanation is the presence of God, also raise this probability. Such experiences may even come to us via  introspection; perhaps it seems that God is “speaking” to me in my mind. This is defeasible, of course, but until it is shown to be faulty in some way, it provides a probabilistic lift to the God hypothesis.

Skeptics, Don’t Worry!

This accumulating evidence by no means settles the issue or “proves” there is a God. Several other factors come into play which may “cancel out” the sorts of evidence I’ve described. First, there’s plenty of evidence against God as well. Two examples: the apparent existence of unnecessary suffering in the world, and perhaps the confusion about God that persists in the world. These may counter evidence in favor of God. (Whether they are enough to outweigh the evidence in God’s favor, is debatable.) Second, our cognitive faculties can make mistakes. We can “perceive” things that aren’t there and “infer” things that don’t follow logically. Surely some of what we think supports our belief in God will turn out to be faulty. (Note: this also applies to any support I might have for atheism.)

Skeptics may also worry about really weird cases where people claim to have evidence. UFO sightings (and abductions), ghost encounters, and other bizarre phenomena also involve alleged evidence. Must we also concede that their beliefs are evidence-based? Well, perhaps. If I’m concerned about a claim of this sort, or about a Christian who claims to witness a miracle, I will investigate. I’ll use the same general approach as Prof. Kirke in The Lion, the Witch, and the Wardrobe, when he was presented with Lucy’s fantastic tale about visiting Narnia.

“How do you know?” he asked, “that your sister’s story is not true?”
“Oh, but –” began Susan, and then stopped. . . “But Edmund said they had only been pretending.”
“That is a point,” said the Professor, “which certainly deserves consideration; very careful consideration. For instance–if you will excuse me for asking the question–does your experience lead you to regard your brother or your sister as the more reliable? I mean, which is the more truthful?”
“That is a point,” said the Professor, “which certainly deserves consideration; very careful consideration. For instance–if you will excuse me for asking the question–does your experience lead you to regard your brother or your sister as the more reliable? I mean, which is the more truthful?”
“That’s the funny thing about it, Sir,” said Peter. “Up till now, I’d have said Lucy every time.” 
“And what do you think, my dear?” said the Professor, turning to Susan.
“Well,” said Susan, “in general, Id’ say the same as Peter, but this couldn’t be true–all this about the wood and the Faun.”
“That is more than I know,” said the Professor, “and a charge of lying against someone whom you have always found truthful is a very serious thing; a very serious thing indeed.”
“We were afraid it mightn’t even be lying,” said Susan. “We thought there might be something wrong with Lucy.”
“Madness, you mean?” said the Professor quite coolly. “Oh, you can make your minds easy about that. One has only to look at her and talk to her to see that she is not mad.” [The children don’t know what to think at this point!]
“Logic!” said the Professor half to himself. “Why don’t they teach logic at these schools?”
2

Now, before you dismiss this example as fanciful fiction and irrelevant, consider what is going on. The Professor simply asks the children to examine how they formed their beliefs, and urges them to apply logic, no matter where it leads.  As I will explain below, there is no rational, unprejudiced way to rule out supernatural explanations prior to unbiased examination.

Misleading Evidence

As I have said, having evidence doesn’t settle the issue. Sometimes, even when we follow the evidence, this rational method fails us. How can this happen? Evidence can mislead us. According to Princeton philosopher Thomas Kelly,

 E is misleading evidence for p just in case (i) E is evidence for p and (ii) p is false. Thus, misleading evidence is genuine evidence in that it satisfies the conditions for being evidence (whatever those conditions turn out to be). In this respect, it contrasts with apparent evidence or fake evidence, which seem to satisfy the conditions for being evidence but do not. The fact that misleading evidence is genuine evidence is why beliefs based on misleading evidence can be reasonable, given that what it is reasonable to believe depends on one’s evidence.3

evidence

So if it turns out there are no gods, then all the theist’s evidence was misleading, like evidence used for a false conviction in a court. But before the skeptic proclaims our evidence misleading, she should consider a couple of thoughts.

  1. We can’t know that our evidence for God is misleading without first knowing whether God exists! This means that a skeptic cannot rationally say that a theist has no evidence, nor can she say that the theists’ evidence is misleading, unless the skeptic has first proven that God does not exist. And even if the theist turns out to be wrong, she may still be quite rational. You might have a worry like this: “But does this also imply that I don’t know if my evidence is legitimate unless I can prove God’s existence?” The rational approach, it seems to me, is this: as long as the evidence points toward a hypothesis, and there are no live defeaters (see below), then we should consider it legitimate. Without this assumption, science, law, etc. would be impossible. 
  2. The skeptic certainly can work to show that the theists’ evidence is fake or apparent evidence (rather than misleading). The best way to do this is by introducing defeaters, either by showing that the means of acquiring the evidence was flawed or unreliable, or that the evidential belief is itself false. But one must be careful to avoid circular reasoning here. For example, one cannot argue that (A) religious experience is fake/unreliable because (B) there is no God, since God’s existence is the very claim under dispute. Arguing this way would be like the following exchange. Sally: The earth is flat. Harry: But photographs from space show a spherical earth. Sally: No, those are fakes. Harry: Why do you think they’re fakes? Sally: Because the earth is flat! That is circular reasoning. What Sally ought to do is give an independent reason to think that Harry’s perception is unreliable or that his evidence is “fake.”
flat earth, evidence

Conclusion

Skeptics and believers both should recognize that evidence for God abounds. The task of the careful thinker is to evaluate the quality of the evidence and weigh it against counter evidence. If a person’s total evidence significantly raises the probability that God exists, isn’t defeated, and isn’t swamped by counter evidence, then belief in God can be quite rational.