The Buddha never placed unconditional demands on anyone's faith. And for anyone from a culture where the dominant religions do place such demands on one's faith, this is one of Buddhism's most attractive features. We read his famous instructions to the Kalamas, in which he advises testing things for oneself, and we see it as an invitation to believe, or not, whatever we like. Some people go so far as to say that faith has no place in the Buddhist tradition, that the proper Buddhist attitude is one of skepticism.

But even though the Buddha recommends tolerance and a healthy skepticism toward matters of faith, he also makes a conditional request about faith: If you sincerely want to put an end to suffering — that's the condition — you should take certain things on faith, as working hypotheses, and then test them through following his path of practice.

There's a hint of this need for faith even in the discourse to the Kalamas:

The first few phrases in this passage, refuting the authority of scripture and tradition, are so strikingly empirical that it's easy to miss the phrase buried further on, asserting that you have to take into account what's praised by the wise. That phrase is important, for it helps to make sense of the Buddha's teachings as a whole. If he had simply wanted you to trust your own unaided sense of right and wrong, why would he have left so many other teachings?

So the Buddha's advice to the Kalamas is balanced: Just as you shouldn't give unreserved trust to outside authority, you can't give unreserved trust to your own logic and feelings if they go against the genuine wisdom of others. As other early discourses make clear, wise people can be recognized by their words and behavior, but the standards for wisdom are clearly measured against the Buddha and his noble disciples, people who've already touched awakening. And the proper attitude toward those who meet these standards is faith.

Repeatedly the Buddha stated that faith in a teacher is what leads you to learn from that teacher. Faith in the Buddha's own Awakening is a requisite strength for anyone else who wants to attain Awakening. As it fosters persistence, mindfulness, concentration, and discernment, this faith can take you all the way to the deathless.

So there's a tension in the Buddha's recommendations about faith and empiricism. I've discussed this point with many Asian Buddhists, and few of them find the tension uncomfortable. But Western Buddhists, raised in a culture where religion and faith have long been at war with science and empiricism, find the tension very disconcerting. In discussing the issue with them over the past several years, I've noticed that they often try to resolve it in the same ways that, historically, the tension between Christian faith and scientific empiricism has been resolved in our own culture. Three general positions stand out, not only because they are the most common but also because they are so clearly Western. Consciously or not, they attempt to understand the Buddha's position on faith and empiricism in a way that can be easily mapped onto the modern Western battle lines between religion and science.

The first interpretation has its roots in the side of Western culture that totally rejects the legitimacy of faith. In this view, the Buddha was an embodiment of the Victorian ideal of the heroic agnostic, one who eschewed the childish consolations of faith and instead advocated a purely scientific method for training and strengthening one's own mind. Because his method focused entirely on the present moment, questions of past and future were totally irrelevant to his message. Thus any references to faith in such issues as past karma, future rebirth, or an unconditioned happiness separate from the immediate input of the senses are later interpolations in the texts, which Buddhist agnostics, following the Buddha's example, should do their best to reject.

The second interpretation has roots in the side of Western culture that has rejected either the specifics of Christian faith or the authority of any organized religion, but has appreciated the emotion of faith as an essential requirement for mental health. This view presents the Buddha as a Romantic hero who appreciated the subjective value of faith in establishing a sense of wholeness within and interconnectedness without. Tolerant and opposed to dogmatism, he saw the psychological fact of a living faith as more important than its object. In other words, it doesn't matter where faith is directed, as long as it's deeply felt and personally nourishing. Faith in the Buddha's Awakening means simply believing that he found what worked for himself. This carries no implications for what will work for you. If you find the teaching on karma and rebirth comforting, fine: Believe it. If not, don't. If you want to include an all-powerful God or a Goddess in your worldview, the Buddha wouldn't object. What's important is that you relate to your faith in a way that's emotionally healing, nourishing, and empowering.

Because this second interpretation tends to be all-embracing, it sometimes leads to a third one that encompasses the first two. This interpretation presents the Buddha as trapped in his historical situation. Much like us, he was faced with the issue of finding a meaningful life in light of the worldview of his day. His views on karma and rebirth were simply assumptions picked up from the crude science of ancient India, while his path of practice was an attempt to negotiate a satisfying life within those assumptions. If he were alive today, he would try to reconcile his values with the discoveries of modern science, in the same way that some Westerners have done with their faith in monotheism.

The underlying assumption of this position is that science is concerned with facts, religion with values. Science provides the hard data to which religion should provide meaning. Thus each Buddhist would be performing the work of a Buddha by accepting the hard facts that have been scientifically proven for our generation and then searching the Buddhist tradition — as well as other traditions, where appropriate — for myths and values to give meaning to those facts, and in the process forging a new Buddhism for our times.

Each of these three interpretations may make eminent sense from a Western point of view, but none of them do justice to what we know of the Buddha or of his teaching on the role of faith and empiricism on the path. All three are correct in emphasizing the Buddha's unwillingness to force his teachings on other people, but — by forcing our own assumptions onto his teachings and actions — they misread what that unwillingness means. He wasn't an agnostic; he had strong reasons for declaring some ideas as worthy of faith and others as not; and his teachings on karma, rebirth, and nirvana broke radically with the dominant worldview of his time. He was neither a Victorian nor a Romantic hero, nor was he a victim of his times. He was a hero who, among other things, mastered the issue of faith and empiricism in his own way. But to appreciate that way, we first have to step back from the Western cultural battlefield and look at faith and empiricism in a more basic context, simply as processes within the individual mind.

There, they play their major roles in the psychology of how we decide to act. Although we like to think that we base our decisions on hard facts, we actually use both faith and empiricism in every decision we make. Even in our most empirically based decisions, our vision is hampered by our position in time. As Kierkegaard noted, we live forwards but understand backwards. Any hard-headed business entrepreneur will tell you that the future has to be taken on faith, no matter how much we know of the past. What's more, we're often forced into decisions where there's no time or opportunity to gather enough past facts for an informed choice. At other times we have too many facts — as when a doctor is faced with many conflicting tests on a patient's condition — and we have to go on faith in deciding which facts to focus on and which ones to ignore.

However, faith also plays a deeper role in many of our decisions. As William James once observed, there are two kinds of truths in life: those whose validity has nothing to do with our actions, and those whose reality depends on what we do. Truths of the first sort — truths of the observer — include facts about the behavior of the physical world: how atoms form molecules, how stars explode. Truths of the second sort — truths of the will — include skills, relationships, business ventures, anything that requires your effort to make it real. With truths of the observer, it's best to stay skeptical until reasonable evidence is in. With truths of the will, though, the truth won't happen without your faith in it, often in the face of unpromising odds. If you don't believe that democracy will work in your nation, it won't. If you don't believe that becoming a pianist is worthwhile, or that you have the makings of a good pianist, it won't happen. Truths of the will are the ones most relevant to our pursuit of true happiness. Many of the most inspiring stories in life are of people who create truths of this sort when a mountain of empirical evidence is against them. In cases like this, the truth requires that faith actively discount the immediate facts.

If we dig even deeper into the psychology of decision-making, we run into an area for which no scientific evidence can offer any proof: Do we actually act, or are actions an illusion? Are our acts already predetermined by physical laws or an external intelligence, or do we have free will? Are the results of our acts illusory? Are causal relationships real, or only a fiction? Even the most carefully planned scientific experiment could never settle any of these issues, and yet once we become aware of them we have to take a stand on them if we want to continue putting any energy into our thoughts, words, and deeds.

These were the areas where the Buddha focused his teachings on empiricism and faith. Although his first noble truth requires that we observe suffering until we comprehend it, we have to take on faith his assertion that the facts we observe about suffering are the most important guide for making decisions, moment by moment, throughout life. Because his third noble truth, the cessation of suffering, is a truth of the will, we have to take it on faith that it's a possible goal, a worthwhile goal, and that we're capable of attaining it. And because the fourth noble truth — the path to the cessation of suffering — is a path of action and skill, we have to take it on faith that our actions are real, that we have free will, and yet that there's a causal pattern to the workings of the mind from which we can learn in mastering that skill. As the Buddha said, the path will lead to a direct experience of these truths, but only if you bring faith to the practice will you know this for yourself. In other words, "faith" in the Buddhist context means faith in the ability of your actions to lead to a direct experience of the end of suffering.

The Buddha offered these teachings to people seeking advice on how to find true happiness. That's why he was able to avoid any coercion of others: His teachings assumed that his listeners were already involved in a search. When we understand his views on what it means to search — why people search, and what they're searching for — we can understand his advice on how to use faith and empiricism in a successful search. The best way to do this is to examine five of his similes illustrating how a search should be conducted.

The first simile illustrates search in its most raw and unfocused form:

The twisting of his body stands for the way we react to suffering. We don't bother to ask if our suffering is predetermined or our actions have any hope of success. We simply put up a struggle and do what we can to escape. It's our natural reaction.

The Buddha taught that this reaction is twofold: We're bewildered — "Why is this happening to me?" — and we search for a way to put an end to the suffering. When he stated that all he taught was suffering and the end of suffering, he was responding to these two reactions, providing an explanation of suffering and its end so as to do away with our bewilderment, at the same time showing the way to the end of suffering as a way of satisfying our search. He had no use for the idea — often advanced by later writers in the Buddhist tradition — that our suffering comes from our struggle to resist suffering; that the search for an end to suffering is precisely what keeps us from seeing the peace already there. In the light of the above simile, simply relaxing into a total acceptance of the moment means relaxing into the prospect of being burned alive. The present keeps morphing into the future, and you can't turn a blind eye to where it's taking you.

This simile also explains why the idea of a Buddhism without faith holds little appeal for people suffering from serious illness, oppression, poverty, or racism: Their experience has shown that the only way to overcome these obstacles is to pursue truths of the will, which require faith as their rock-solid foundation.

The second simile:

This simile shows the perils of looking for true happiness in the wrong place: in sensual pleasures. If your happiness depends on anything other people can take away from you, you're putting yourself in danger. As the Buddha notes, we hope for happiness in sensual pleasures not because they've ever really satisfied us but because we can't imagine any other escape from pain and suffering. If we allowed ourselves to believe that there is another alternative, we'd be more willing to question our strong faith in our cravings and attachments, more willing to look for that alternative and give it a try. And, as the third simile argues, if we look in the right way, we'll find it.

The Buddha taught this simile in response to an assertion that there is nothing a human being can do to attain release from suffering. We can attain it, he said, as long as we follow the right method, like the person pulling at the udder of the cow.

The right method starts with right understanding, and this is where faith in the Buddha's Awakening comes in. As the Buddha once stated, he didn't tell us everything he awakened to. What he told was like a handful of leaves; what he learned was like the leaves in the forest. Still, the leaves in the handful contained all the lessons that would help others to awaken; right understanding begins with learning what those specific lessons are.

The most important lesson, and the most important item of faith, is simply the fact of the Awakening itself. The Buddha achieved it through his own efforts, and he did so, not because he was more than human, but because he developed mental qualities that we each have the potential to develop. To have faith in his Awakening thus means having faith in your own potential for Awakening.

However, the specifics of what he learned in his Awakening are important as well. It's not simply the case that he found what worked for him, while what works for you may be something else entirely. No matter how much you twist a cow's horn, it'll never produce milk. The Buddha's insights penetrated into how things work, what it means for them to work. These insights apply to everyone throughout time.

When summarizing his Awakening in the most condensed form, the Buddha focused on a principle of causality that explains how we live in a world where patterns of causality fashion events, and yet those events are not totally predetermined by the past.

The principle is actually a dual one, for there are two kinds of causality interweaving in our lives. The first is that of a cause giving results in the immediate present: When this is, that is; when this isn't, that isn't. When you turn on a stereo, for example, the noise comes out; when you turn it off, the noise stops. The second type of causality is that of a cause giving results over time: From the arising of this comes the arising of that; from the cessation of this comes the cessation of that. If you study now, you'll have knowledge long into the future. If you damage your brain, the negative effects will be long-term as well.

Applied to karma, or intention, the dual principle means this: Any moment of experience consists of three things: (1) pleasures and pains resulting from past intentions, (2) present intentions, and (3) pleasures and pains resulting from present intentions. Thus the present is not totally shaped by the past. In fact, the most important element shaping your present experience of pleasure or pain is how you fashion, with your present intentions, the raw material provided by past intentions. And your present intentions can be totally free.

This is how there's free will in the midst of causality. At the same time, the pattern in the way intentions lead to results allows us to learn from past mistakes. This freedom within a pattern opens the way to a path of mental training that can lead to the end of suffering. We practice generosity, virtue, and meditation to learn the power of our intentions and in particular to see what happens as our intentions grow more skillful, so skillful that present intentions actually stop. Only when they stop can you prove for yourself how powerful they've been. And the spot where they stop is where the unconditioned — the end of suffering — is found. From there you can return to intentions, but you're no longer their captive or slave.

In presenting his teachings on karma and suffering to his listeners, the Buddha would offer empirical evidence to corroborate them — noting, for instance, how your reaction to another person's misery depends on how attached you are to that person — but he never attempted to back these teachings with full-scale empirical proof. In fact, he heaped ridicule on his contemporaries, the Jains, who attempted to prove their more deterministic teaching on karma by claiming that all those who kill, steal, lie, or engage in illicit sex will suffer from their actions here and now. "Haven't you seen the case," the Buddha asked, "where a man is rewarded by a king for killing the king's enemy, for stealing from the king's enemy, for amusing the king with a clever lie, for seducing the king's enemy's wife?" Even though the basic principle of karma is simple enough — skillful intentions lead to pleasure, unskillful intentions to pain — the dual principle of causality through which karma operates is so complex, like a Mandelbrot set, that you would go crazy trying to nail the whole thing down empirically.

So instead of an empirical proof for his teaching on karma, the Buddha offered a pragmatic proof: If you believe in his teachings on causality, karma, rebirth, and the four noble truths, how will you act? What kind of life will you lead? Won't you tend to be more responsible and compassionate? If, on the other hand, you were to believe in any of the alternatives — such as a doctrine of an impersonal fate or a deity who determined the course of your pleasure and pain, or a doctrine that all things were coincidental and without cause — what would those beliefs lead you to do? Would they allow you to put an end to suffering through your own efforts? Would they allow any purpose for knowledge at all? If, on the other hand, you refused to commit to a coherent idea of what human action can do, would you be likely to see a demanding path of practice all the way through to the end?

This was the kind of reasoning that the Buddha used to inspire faith in his Awakening and in its relevance to our own search for true happiness.

The fourth simile stresses the importance of not settling for anything less than the genuine thing:

Faith in the possibility of nirvana — the heartwood of the path — is what keeps you from getting waylaid by the pleasures of the sapwood and bark: the gratification that comes from being generous and virtuous, the sense of peace, interconnectedness, and oneness that comes with strong concentration. Yet, surprisingly, modern discussions of the role of faith in the Buddha's teachings rarely mention this point, and focus on faith in karma and rebirth instead. This is surprising because nirvana is much less related to our everyday experience than either karma or rebirth. We see the fruits of our actions all around us; we see people being born with distinct personalities and differing strengths, and it's only a short leap to the idea that there's some connection between these things. Nirvana, however, isn't connected to anything we've experienced at all. It's already there, but hidden by all our desires for physical and mental activity. To touch it, we have to abandon our habitual attachment to activity. To believe that such a thing is possible, and that it's the ultimate happiness, is to take a major leap.

Many in the Buddha's time were willing to take the leap, while many others were not, preferring to content themselves with the branches and sapwood, wanting simply to learn how to live happily with their families in this life and go to heaven in the next. Nirvana, they said, could wait. Faced with this honest and gentle resistance to his teaching on nirvana, the Buddha was happy to comply.

But he was less tolerant of the stronger resistance he received from brahmas, heavenly deities who complacently felt that their experience of limitless oneness and compassion in the midst of samsara — their sapwood — was superior to the heartwood of nirvana. In cases like this he used all the psychic and intellectual powers at his disposal to humble their pride, because he realized that their views totally closed the door to Awakening. If you think that your sapwood is actually heartwood, you won't look for anything better. When your sapwood breaks, you'll decide that heartwood is a lie. But if you realize that you're using bark and sapwood, you leave open the possibility that someday you'll go back and give the heartwood a try.

Of course, it's even better if you can take the Buddha's teachings on nirvana as a direct challenge in this lifetime — as if he were saying, "Here's your chance. Can you prove me wrong?"

The fifth simile:

In explaining this simile, the Buddha said that all the preliminary steps of the practice — going into the wilderness as a monastic; adhering to the precepts; developing restraint, contentment, and strong concentration; seeing past lives and gaining vision of the beings of the cosmos dying and being reborn in line with their karma — are simply footprints and scratch marks of the Buddha's Awakening. Only when you have your own first taste of Awakening, having followed his path, do you really know that your faith in his Awakening was well placed. Touching the dimension where suffering ends, you realize that the Buddha's teachings about it were not only true but also useful: He knew what he was talking about and was able to point you there as well.

What's interesting about this simile is the way it combines healthy faith with honest skepticism. To act on this faith is to test it, the way you'd test a working hypothesis. You need faith to keep following the footprints, but you also need the honesty to recognize where faith ends and knowledge begins. This is why, in the Buddhist context, faith and empiricism are inseparable. Unlike a monotheistic religion — where faith centers on the power of another — faith in the Buddha's Awakening keeps pointing back to the power of your own actions: Do you have enough power over your intentions to make them harmless? Do harmless intentions then give you the freedom to drop intention entirely? The only way you can answer these questions is by being scrupulously honest about your intentions, to detect even the slightest traces of harm, even the slightest movement of intention itself. Only then will you know the deathless, totally unconditioned by intention, for sure. But if you claim to know things that you don't, how can you trust yourself to detect any of these things? You need to make your honesty worthy of your faith, testing its assumptions until you find true knowledge in the test.

This is why science will never be able to pass valid judgment on the truths of Awakening, for the path deals in matters that outside experimenters can't reach. Although others may sympathize with your suffering, the suffering itself is an experience you can share with no one else. The honesty and skillfulness of your intentions is an affair of your internal dialogue, something that is also purely your own. Scientists can measure the neurological data indicating pain or intentional activity, but there's no external measurement for how the pain feels, or how honest your intentional dialogue may be. And as for the deathless, it has no physical correlates at all. The closest that outside empirical measurement can get is to pictures of the footprints on the ground and the marks in the trees.

To get to the bull elephant, you have to do what the Buddha's disciple Sariputta did. He kept following the path, without jumping to dishonest conclusions, until he saw the elephant within. Then, when the Buddha asked him, "Do you take it on faith that these five strengths — faith, persistence, mindfulness, concentration, and discernment — lead to the deathless," Sariputta could answer honestly, "No, I don't take it on faith. I know."

As Sariputta stated in another discourse, his proof was experiential but so inward that it touched a dimension where not only the external senses but even the sense of the functioning of the mind can't reach. If you want to confirm his knowledge you have to touch that dimension in the only place you can access it, inside yourself. This is one of two ways in which the Buddha's method differs from that of modern empiricism.

The other has to do with the integrity of the person attempting the proof.

As in science, faith in the Buddha's Awakening acts like a working hypothesis, but the test of that hypothesis requires an honesty deeper and more radical than anything science requires. You have to commit yourself — every variation on who you feel you are — totally to the test. Only when you take apart all clinging to your inner and outer senses can you prove whether the activity of clinging is what hides the deathless. The Buddha never forced anyone to commit to this test, both because you can't coerce people to be honest with themselves, and because he saw that the pit of burning embers was coercion enough.