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The Truth about Religion: Using Evidence to Decide What to Believe

The Truth about Religion: Using Evidence to Decide What to Believe

Religions tell stories about the world. We want to know if there is truth in those stories. How can we find this out?


Among the things we all care about is the truth. No one is indifferent to the truth. One reason for this is that we cannot get what we want without it. We learn this as young children. If you want hot water, you need to know which the correct faucet is. To get a book from the library, you need to know where your library card is. To stop your friend’s tears, you need to know why he is crying. Accurate information – truth – is crucial to navigating life’s challenges.

As we grow older, the same lesson is repeated endlessly. To get a college degree, we need to know the right answers to the exam questions. To catch a plane, we need to know the flight schedule. To make a living as a doctor, we need to know medicine. To get someone to say yes, we need to know the rights words and deeds.

Another way to see the importance of the truth is this. Imagine a new invention – a dream machine. When you are connected to this machine, it gives you dreams. The owner is offering it to anyone to use, free of charge. You tell him what dreams you want to have and he will program the machine to deliver those dreams. There is only one catch: once you are attached to the machine they put you on a life-support system and you stayed attached for the rest of your life. You can receive any dreams you like, as thrilling, filled with pleasure and achievement as you can imagine. But you never get back to the real world.

Would you take it? After all, your real life will not be nearly as exciting, pleasurable or fulfilling as the dream. Even so, I’m willing to guess that deep down you know you wouldn’t feel right attaching yourself to the machine. Deep down, most of us sense that we want to make a difference in the real world. We do not live only for what we experience. We are also living for what we want to do. What most people want to do is to have a real effect on the lives of real people. The dream machine makes that impossible.

And if you would take the offer, I think I can show you that you still care about acting in the real world. Imagine that you have the ability to cure cancer and are prepared to make the effort to do so. And now the owner of the dream machine offers you a dream in which you will do exactly the same thing – in the dream you will cure cancer. In that case no one would choose the dream machine because no one will be cured! So everyone cares to some degree about affecting the real world.

The only way to know how to make a difference in the real world is to know the truth. Without the truth, we live in a (partial) dream. Without the truth, we only “guess” that our actions affect people in a certain way. In reality, the effect could be very different. For example, doctors used to bleed people when they had a fever. They believed this would help them. In fact, it does not help – and might do some harm. Imagine a doctor, on his deathbed, discovering that this treatment, which he used all his life, really hurt people. How would he feel? He didn’t know the truth and therefore he couldn’t possibly have made correct decisions throughout life to help others.

We’ve seen that knowing the truth and using it to direct our actions is important to all of us. It is important because we need the truth to get the other things we want, and one of the things we want is to make a difference in the real world.

Still, truth isn’t the only thing that counts. Other things are important also. We need to add truth to the list we started with – health, education and all the rest. And once we add it, we then are faced with a crucial question: What happens if truth conflicts with some of the other things we care about? What do we do then?

This can happen in many different ways. Here are a few examples:

  • Some people delude themselves that others are their friends because they cannot face the truth that they are unpopular.
  • Some continue to try to be the very best at their area of interest rather than face the fact that they do not have that ability.
  • Some gamble away their money believing that next time they will be lucky.

In each of these cases, a person holds on to a falsehood because facing the truth is too painful. Still, it is clear that he is making a mistake. It would be far better to acknowledge the truth and live with the consequences. The reason is that in this way we will get more of what we care about. To refuse to face the truth will only add to misery. If a person continues to think he is popular, he will not make the changes necessary to really become popular. If he does not give up his unrealistic dreams, he will not focus on challenges that he can really meet.

In almost all cases the best decision is the one that is based on the facts – on truth.

This is what usually happens if the truth is disregarded: things get worse and our goals move even further away. Truth is so useful that (in almost all cases) ignoring it is not the best policy.

There could be exceptions. Sometimes, finding the truth is too expensive or dangerous. Sometimes, the decision is so insignificant that getting it wrong does not matter. Sometimes, facing the truth would be so disruptive right now that it is best put off for a while.

Still, in almost all cases the best decision is the one that is based on the facts – on truth. Let’s give names to these two options:

  • Putting truth first we will call “realism”
  • Putting other things we care about first we will call “opportunism”

What we have seen is that realism usually takes precedence over opportunism.

Truth and Responsibility

One of the things we may care about is fulfilling our responsibilities. Here, too, we need the truth.

If I am responsible for the welfare of a child, I need to know a certain amount of medicine, nutrition, psychology and education. Without that information, I cannot care responsibly for the child.

If I have money to give to charity, who should I give it to? Who is presenting honest claims and who is a fake?

Knowing the truth is necessary for fulfilling our responsibilities.

Here, again, there could be exceptions. Suppose I have to make a decision in the next twenty-four hours and it will take a week to find out the truth. It could be that waiting is worse than getting the decision wrong.

Still, in normal circumstances finding the truth is necessary for making good decisions and taking responsible actions.

Here, again, realism comes first.

Truth and Religion

The importance of truth for the success of our actions, and for fulfilling our responsibilities in particular, applies directly to religion. Why?

Many religions tell stories. These stories describe where the world came from, where it is going and what is guiding it on its path. They describe the real essence of the human being. They record important religious events – prophecy, divine inspiration, miracles, the founding of religious concepts and customs. They record important human events – the origin of peoples and cultures, migrations, wars, settlements. They codify laws that have been communicated to mankind from the divine.

Here is the key point. Typically, such a religion will base its directions for living on its own essential story. The reason for the laws, customs, values and beliefs of the religion is that the world is built in this particular way and that these events occurred. This, of course, depends upon the story being true. If the story of a particular religion is in fact true (and so the religion accurately understands and describes the reality we live in), then following its terms will give the most successful and responsible life. If the story is not true, then following its way of life cannot be expected to lead to success. Since we care about the success of our actions, including the fulfillment of our responsibilities, we have an interest in following the religion that has the best claim to be true. Otherwise, we risk living lives which are counterproductive and irresponsible.

Suppose, for example, that the Creator of the universe revealed Himself to the Jewish People at Sinai and told them to keep the Sabbath. In that case, keeping the Sabbath is one of the best things a Jew can do. One cannot expect to have a better life by violating the will of the Creator who created life itself!

Therefore, it becomes crucial to find out the truth:

  • Did the Creator really command the Sabbath at Sinai? If He did, then our lives need to reflect that truth.
  • Did He really command the honor of parents? Then that truth will impact on our relationship with our parents.

A religion is more than a story. Religions include moral principles, ceremonies, poetry, music, social institutions and practices such as prayer and meditation. All these have value. They may succeed in inspiring people and focusing their lives on truly important goals.

If truth exists and we ignore it, we are likely to waste our entire lives climbing up the wrong tree.

Still, let’s not lose focus on the essential point: if the story of a religion is not true, the benefits of the truth we saw above are lost. In addition, the story is often given as the reason for accepting the moral principles and the rest. If the story is not true, the reason is lost. Living in terms of a false story will result in much wasted, counter-productive effort.

The priority of living with the truth means that we have to find out what the truth is. If truth exists and we ignore it, we are likely to waste our entire lives climbing up the wrong tree. Therefore, the first order of business in thinking about religion is to be a realist – to find out whether there is any religious truth, and if so, which one. This must guide our decisions.

How to Find the Truth

Religions tell stories about the world. We want to know if there is truth in those stories. How can we find this out?

In principle, we can do this the same way we find out whether anything is true. We look for evidence, compare alternatives and judge what is most likely to be true. Just as we do this in the rest of life, we can and should do this in trying to discover religious truth.

There will be two objections to this approach:

  1. First, it will be said that religion is special. Religion deals with subjects that cannot be discovered by looking for evidence. What kind of evidence will decide whether there is an infinite, spiritual Creator, or an after-life for the soul, or that a Messiah will come?

The answer to this objection is to remember the contents of the stories we want to check. Yes, part of the story deals with the Creator, the after-life, the Messiah and moral rules. That part may be beyond direct evidence. However, part of the story deals with historical events that can be investigated by ordinary techniques. For instance, the Jewish story relates a national revelation experience and individual prophecies, national miracles like the plagues in Egypt and the crossing of the Red Sea, the lives of the Patriarchs and Matriarchs and the experiences of King David. There is no reason we cannot find evidence for descriptions like these.

  1. The second objection will be that such a project is inherently intolerant. If we look for – and find – religious truth, will we not have to brand any other competing religious idea as false? Some will say that is bigoted. Surely all religions are equally good, true, valid, valuable and should be given equal respect!

Here, I think we have to bite the bullet. Yes, to look for the truth means that false alternatives will have to be rejected. And since religions contradict one another, they cannot all be completely true. For example:

  • Many Christian groups believe a certain man was G-d.
  • Islam rejects that idea and says the Muhammad was the greatest prophet.
  • Judaism rejects both those ideas.

And so it goes for all the major world religions.

To look for the truth means that false alternatives will have to be rejected. And since religions contradict one another, they cannot all be completely true.

This means that since we are looking for truth in religion, some ideas of some religions will have to be rejected. If someone is really committed to the idea that all religions are equally good, true, valuable, etc. even before he starts the investigation, then he should stop right now.

However, notice what he risks. If, in fact, there is good evidence that some religious ideas are true and some are false, then he is going to lose the truth by his refusal to look at the evidence. We know that ignoring the truth will almost always prevent us from achieving what we care about, including being responsible. This applies to the truths claimed by religious traditions just as it applies to any claims to truth (giving proper medical help, financial planning, etc.).

In any case, we cannot take this uncritical, “tolerant” attitude across the board. There are people who deny the Holocaust. Are their opinions worthy of respect? Surely not!

Why not? Because they ignore all the evidence. Well, if there is sufficient evidence for the truth of some religion, then it is unreasonable to ignore it. To claim that all religions are equally good, etc. in spite of the evidence is as unreasonable as disbelieving the Holocaust. Facts – the truth – is a value in and of itself. Searching for it is valuable for the many benefits it brings, and for its very essence itself.

So, we are going to be honest and responsible and look for evidence for religious truth. This looks like a very large project. There are eight major world religions – Judaism, Christianity, Islam, Hinduism, Buddhism, Confucianism, Taoism and Shinto. To be fair, do we not have to give each of them a try? That would mean we would have to learn all of them and check the evidence for each – a very long project! In theory, yes, that is what the project would require.

However, in practice, it is much easier. The reason will become clear when we see how the evidence will be found.

How to Gather Evidence

We are trying to discover whether any religious story is true. To do this, we look at the evidence and judge how well it supports the various stories. The first step in making this judgment is to make sure that each story has some evidence in its favor. To take an idea seriously it must have some positive evidence.

It is not enough that the idea could be true. Many ideas could be true. Are there any dogs with wings – anywhere in the whole universe? No one can prove otherwise. It could be true. But that is not a good enough reason to believe in dogs with wings. We need some positive evidence that they exist before we accept them.

The reason we need positive evidence is that we are going to use the truth as a guide how to act. We cannot act on every idea that might possibly be true. There are too many such ideas, and some require actions that would contradict the actions required by others. So we act on what the evidence indicates is likely to be true.

Surprisingly, there are religions that do not possess any evidence that their stories are true. They include the far-Eastern religions of Confucianism and Taoism. Those religions offer themselves as beautiful, inspiring, noble ways of life. They promise certain qualities of feeling and insight. In other words, they speak to some of the things we care about. However, they do not even pretend to offer evidence to think their stories are true. That being so, our project of finding the truth does not apply to them.

Notice that, for all we know, their stories might be true. Our reason for omitting them is not that we know they are false. We cannot prove there are no dogs with wings either. Our reason for omitting them is that they give us no reason to think they are true.

The Need for Selective Evidence

The second step is to make sure that the evidence is selective – that the evidence offered in favor of one religion’s story counts against the stories of the other religions. This is a tricky point. Whenever we are looking for the truth there are alternative possibilities that need to be considered. While our understanding is limited and we can never hope to know complete truth, we want to get the best possible understanding of the truth that we can achieve. In other words, we want to know which of the alternatives is the most likely to be true. We want the evidence to work for some and against others. If the evidence that we find supports all of the alternatives, it does not help us make our decision which alternative to accept.

In science, this is called a crucial experiment. We want an experiment for which competing theories predict different results. Then, when we perform the experiment, some theories will be supported and others undermined. If all the theories predict the same results, then the experiment does not tell us which are the superior theories.

For religions, we have to check that others cannot accept the evidence offered for one. If they can, it does not tell us which religions are most likely to be true.

Some religions offer evidence that is not selective in this way. For example, some Muslim sources consider the rapid conquest of Arabia and North Africa as evidence of help from Allah. But a non-Muslim could accept that Muslim armies could be very successful in war. His religion, or his secular viewpoint, allows him to explain the Muslim conquests in the way we explain the conquests of the Greeks or the Romans. Since others can accept the fact of Muslim conquest within their (non-Muslim) point of view, that conquest does not show Islam to be more likely true than they are.

Similarly, some see the spread of Christianity to all corners of the world as evidence that it must be true. But a non-Christian will say that many false ideas have been believed by a great many people – polytheism, for example. And even today, the majority of people are not Christians.

Many Muslim sources claim that anyone who learns Arabic well will see for himself that the Quran could only have been written by God. The language and the ideas are clearly divine. Non-Muslims will point out that every religion has followers who “see” that their scriptures are divine. Also, there are numerous scholars of Arabic who know the Quran well and who do not convert to Islam – they are not convinced this “evidence” proves Islam to the detriment of other belief systems.

Some religions offer evidence of truth based upon personal experience. They prescribe a regimen of diet, exercise and meditation. They predict that if you follow the regimen, you will have certain feelings. Indeed, many people who try it report that the predictions do come true! Is that evidence that those religions are true?

Not at all. It shows only that they have some physical or psychological knowledge. They know how people will feel if they follow the regimen. This is not related at all to the story of their religion. The proof is that other religions, with very different stories, can accept their prediction of those feelings. (For example, yes, meditation will usually lower stress and make a person feel “connected,” but that is irrelevant to whether or not the story of a specific religion espousing it is true.) Since different religions, with different stories, can accept the same prediction (diet, exercise and meditation will have beneficial effects), that prediction does not support one story more than the others. The evidence is not selective, and so it does not make their religion more likely true than the others.

The only evidence offered by Hinduism and Buddhism is evidence in certain personal feelings. Since this evidence is not selective, it does not give any reason to think their stories are more likely to be true than any of the others.

The Need for Evident Evidence

This next point might be obvious, but let’s consider it in any case, for the sake of completeness. Suppose someone says that the story of his religion is true. He offers as proof miracles that the founder of the religion performed. For example, Muslims say that Muhammad ascended to heaven in a fiery chariot. That miracle shows that he was a true prophet and that the Quran came from God.

In this case, the critic is free to deny the “evidence.” Only Muslims believe that Muhammad ascended to heaven in a fiery chariot. There is no independent evidence that this happened. Non-Muslims reject the very facts that the Muslims cite as evidence. In order for evidence to count, it has to be agreed upon by all sides. It must really be evident, as the word implies.

Christians often cite the miracles described in their scriptures or experienced in later generations as evidence of the truth of the story of their religion. Non-Christians will not be convinced that those miracles happened at all.

This requirement discounts all the evidence offered by various religions that is not universally accepted to be true. If it is not universally accepted, then it cannot be used as evidence to support the truth of their stories over the stories of other religions.

As we will see (in the remainder of the book), the only religion that offers selective evidence is Judaism. Our project of finding the truth to guide our actions leads us to consider that evidence.

Excerpted from Reason to Believe, by Rabbi Dr. Dovid Gottlieb, one of the greatest contemporary teachers of Judaism. This masterful work presents a powerful and logical explanation to the question: How do we know that Judaism is true? Click here to order.

September 9, 2017

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