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?”

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


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


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.

Is the Kalam Cosmological Argument Persuasive? (Hot Seat, Part 2)

hot seat, persuasive, argument

An atheist (or maybe agnostic?) posed this question to me in the video below. Honestly, I do find the Kalam argument (KCA) powerful, but of course I first encountered it from the perspective of a believer. My response in the video includes more detail. If you aren’t familiar with the KCA, here is a version of it:

  1. Everything that begins to exist has a transcendent cause of its existence.
  2. The universe began to exist at some point in the finite past.
  3. So, the universe has a transcendent cause of its existence.

The video is about 8.5 minutes and features me answering questions at a meeting of atheists and skeptics at the University of Missouri.

Persuasiveness Is Relative?

Here’s a point worth making, I think: the persuasiveness of an argument is relative to the individual. Each of us holds a collection of beliefs and desires inside us. How a new idea appears to us will depend, in large part, on the make-up of that collection. None of us can have exactly the same collection, and thus new ideas appear differently to each of us.

horse, dogFor example, I remember when my daughter Phoebe saw a horse for the first time. At that point, she only had categories for ‘cat’ and ‘dog.’ So, she pointed to the horse and said, “Doggy!” It wasn’t that she needed glasses–she was perceiving the horse according to the collection of beliefs and desires she possessed. In a much more complex way, we perceive and evaluate new ideas according to our collection. Another example: if I approached first a stranger and then my wife with photos of me dunking a basketball, the stranger might respond very differently than my wife. Based on what she knows, she might laugh harder than the stranger.

Be Kind

slow, patienceI appreciate the saying: “Be kind, because everyone you meet is fighting a hard battle.” I propose an epistemic corollary: “Be kind, because everyone you meet is working with a different set of evidence.” This principle encourages me not to get upset with those who disagree with me. Even those who just “can’t see reason,” deserve my patience and charity, since I generally don’t know where they’re coming from. Moreover, when I am slow to understand or accept an argument, I give grace to myself as well.

Here’s a takeaway: don’t be frustrated when others don’t see things the way you do. 

The person you speak with may be believing as well as he or she can, given the information, background, and psychology they have.

But Is It Persuasive?

Ultimately, you’ll have to answer that question for yourself. But I do think that some arguments are better than others, and probably should be persuasive to most reasonable, well-informed people. The KCA falls into that category. That doesn’t mean that a reasonable atheist will immediately become a theist. But it should make the idea of God’s existence a little more plausible.

big bang, evidence, persuasive, KalamThe biggest reason I hear for outright rejection of the KCA is a commitment to Stephen Hawking’s cosmology, or perhaps a denial of Big Bang cosmology. If Hawking is right, then perhaps the universe does not need a transcendent cause. And if the Big Bang model proves incorrect, then maybe the universe had no beginning. Unfortunately, I admit I’m in no position to evaluate these claims scientifically. I’ll let the experts duke it out. But regardless of the science, which changes from decade to decade, there are excellent philosophical reasons to accept both premises of the KCA. Given that, and the expert testimony I am familiar with, I find the KCA powerful.

(For an in-depth discussion of Hawking’s cosmology, listen to my podcast with Dr. Kenny Boyce. For more serious discussion of the KCA, I recommend William Lane Craig’s website, Reasonable Faith. Dr. Craig does an excellent job of responding to critics of the KCA. Here, for example, and here.)