In a dialogue where the Buddha listed the duties of teachers to their students (DN 31), the final and most prominent item on the list was this: that the teacher provide the student with protection in all directions. Of course, this didn’t mean that teachers were duty-bound to follow their students around with shields to ward off potential dangers. Instead, it meant that teachers should provide their students with knowledge that the students could use to protect themselves in every situation. And in a dialogue where the Buddha criticized some teachers of other sects for leaving their students unprotected (AN 3:62), he made clear that protective knowledge was expressed in terms of a duality: clearly seeing the difference between what should and shouldn’t be done.

That’s right: a duality. For all the dualities the Buddha avoided, this was one he adhered to consistently in his role as a responsible teacher.

The need for this kind of protective knowledge is based on the Buddha’s analysis of how we shape our experience. Instead of being a passive recipient of the results of past kamma (karma), we’re proactive: Through our desires—expressed in acts of attention, perception, and intention—we take the input of the senses, which comes from past kamma, and shape it into a present-moment experience. For example, we don’t just passively register the sight of an apple as it occurs. If we’re already looking for food, then by the time we’re aware of the apple, we’ve already decided whether we want to eat it or not. If we’re not looking for food, the apple hardly registers at all because we have our eye out for something else.

The problem is that we’re often ignorant of what we’re doing, so we shape things unskillfully and suffer as a result. And when we suffer, we react in two ways. The first reaction is bewilderment: “Where does this suffering come from?” The second is a search: “Is there anyone who knows a way out of this suffering?” The search explains why people go looking for teachers in the first place. The bewilderment explains why we can easily look to the wrong people for help.

So we need two sorts of protection: protection against ourselves, to overcome our ignorance of what we’re doing; and protection against teachers—and this can include anyone who offers advice, even well-meaning friends and acquaintances—who might wittingly or unwittingly do us harm.

The knowledge that the Buddha offered as protection attacked these problems on many levels—and the word attack is appropriate here. In the Tittha Sutta (“Sectarians,” AN 3:62), he did something that he rarely ever did, which was to seek out other teachers and denounce them sharply for their doctrines. The harm they were causing was that serious. He criticized, in particular, three teachings: that whatever pleasure or pain you experience is (1) determined by past actions, (2) determined by a creator god, or (3) occurs randomly, without cause of condition.

In each case, his criticism was the same: If you adopted any of these teachings, you’d believe yourself powerless in the present moment to change things here and now. You’d have no motivation to think in terms of what should and shouldn’t be done, because the choice would be meaningless. Since all your actions in the present moment, in your eyes, would either be predetermined or ineffectual, the duality between good and evil would be an empty convention.

The Buddha’s argument was the same in each of the three cases, so here are his words on just the first:

In that case, a person is a killer of living beings because of what was done in the past. A person is a thief… uncelibate… a liar… a divisive speaker… a harsh speaker… an idle chatterer… greedy… malicious… a holder of wrong views because of what was done in the past.’ When one falls back on what was done in the past as being essential, there is no desire, no effort (at the thought), ‘This should be done. This shouldn’t be done.’ When one can’t pin down as a truth or reality what should & shouldn’t be done, one dwells bewildered & unprotected.

The implication here is that if a teaching is going to protect you, the first level of protection has to be on the theoretical level. You have to understand that your present actions are free, to at least some extent, to shape the present moment—for good or bad—and to have an impact on the future. This understanding of kamma would then provide you with motivation for looking carefully at what should and shouldn’t be done right now to avoid causing suffering.

And this is precisely the understanding of kamma that the Buddha taught. As he pointed out in the Loṇaphala Sutta (“The Salt Crystal,” AN 3:101), past actions do have an impact on the present moment, but how that impact is experienced is filtered through your present-moment mind-state. This is one of the reasons that Buddhist meditation focuses on being alert to what the mind is doing right now. If you’re sensitive to your present actions, you can shape them well enough to mitigate the influences from any past bad kamma and, through your present skillful kamma, to provide conditions for pleasure and happiness now and into the future.

So the first level of protection lies in the realm of general theory. However, the dualistic knowledge offered by the Buddha doesn’t stop there. It also goes into specific examples of what should and shouldn’t be done, and from there into general principles to be used in judging for yourself what should and shouldn’t be done in instances not covered by the examples.

The examples are offered as rules and precepts, such as the precepts against killing, stealing, illicit sex, lying, and taking intoxicants. Many people don’t like rules, seeing them as small-minded and confining, but it’s hard to argue with some of the rules the Buddha offers for your protection. They give you clear warning signs for when your ignorance is blinding you to behavior that will, in the long term, cause harm. The rules give you objective standards for judging not only your own behavior but also the behavior of people who offer themselves as teachers.

The monks, for example, have a rule that if a monk even suggests to a student—or anyone at all, for that matter—that she would benefit from having sex with him, he has to undergo a penance for six days. During the penance, he is stripped of his seniority and has to confess his offense to all his fellow monks daily. If he hides the offense, then when he’s found out he has to undergo an added probation for as many days as he hid the offense. If he actually has sex with anyone, he’s out—automatically stripped of his status as a monk and prohibited from re-ordaining for the rest of this lifetime.

The existence of these rules doesn’t guarantee that people won’t break them, but they do serve as red flags and to indicate that the Buddha had no tolerance for this sort of behavior. Students aware of these rules would then know for sure when a monk—or any teacher—had stepped out of bounds. If knowledge of these rules were available in all Buddhist communities, it would prevent a lot of confusion and grief.

You sometimes hear the argument that awakened people are beyond observing the precepts because they have abandoned the fetter of “grasping at precepts and practices” (silabbata-paramasa), but this argument is based on a misunderstanding of what “grasping” means here. Actually, as the Vera Sutta (“Animosity,” AN 10:92) shows, people who have abandoned this fetter never intentionally break the precepts. Their precepts are “untorn, unbroken, unspotted, unsplattered, liberating, praised by the observant, ungrasped at, leading to concentration.” The fact that they’re untorn means that they’re observed consistently. “Ungrasped at” means that even though such people are virtuous, they don’t fashion any sense of self around their virtues (MN 78).

This means that awakened people are consistently virtuous, but—unlike ordinary people still grappling with the precepts—they have freed themselves from having to construct an identity around virtue in order to maintain it. In other words, they don’t have to keep reminding themselves of the precepts, but their behavior still falls perfectly in line with what the precepts teach.

As for the general principles the Buddha taught for deciding what should and shouldn’t be done, they start on a very basic level with the instructions he gave to his son, Rahula, on how to purify his actions (MN 61). These boil down to the principle that you judge your actions both by the intentions motivating them and by the results they yield. If you can foresee that an action you want to do will cause harm, either to yourself or to others, you shouldn’t do it. If you don’t foresee harm, you can go ahead and do it but—in line with the power of actions to shape both the present and the future—you have to check for the results of the action both while you’re doing it and after it’s done. If, in the course of doing the action, you find that you’re causing unexpected harm, you stop. If you find out only after the fact that it caused harm, you talk it over with someone more advanced on the path and resolve not to repeat the mistake. This way you gain practical experience, based on your own powers of observation, in mastering the dualistic principle of what should and shouldn’t be done.

The duality of this principle extends to more advanced teachings as well. The four noble truths, for example, are basically dualistic, and not just because four is a double duality. Suffering (the first noble truth) and the end of suffering (the third) are two very different things. You may have heard the Buddha quoted as saying, “I teach one thing and one thing only: suffering and the end of suffering,” which sounds like he’s offering a non-dualistic perspective on suffering and its end. But that wasn’t what he actually said. His actual words were much more straightforward and dualistic: “Both formerly and now, it’s only suffering that I describe, and the cessation of suffering.” (SN 22:86)

And the duties appropriate to the four noble truths show that this is a genuine duality: The origination of suffering (the second noble truth) should be abandoned. The path to the cessation of suffering (the fourth truth) should be developed. Abandoning and developing are two opposite things. And the path is composed of eight right factors clearly differentiated from eight corresponding wrong factors. All of this continues the dualistic pattern of the Buddha’s protective teaching: having a solid grounding for deciding what should and shouldn’t be done.

This pattern extends even to the Buddha’s subtlest teaching, dependent co-arising, his detailed explanation of all the many factors that go into causing suffering. This teaching is sometimes hailed as non-dualistic, and it is true that the Buddha’s explanation of these factors avoids the duality of saying that everything is either a Oneness or a plurality. So to that extent, they are non-dual.

But when the Buddha explained dependent co-arising in detail, he repeatedly presented it in terms of a different duality: how it should and shouldn’t be approached (see, for starters, the many discourses in SN 12). If, when dealing with the factors as they actually present themselves, you approach them in ignorance, you cause suffering. If you approach them in terms of knowledge of the four noble truths and their duties, you bring suffering to an end.

So here, again, even on the most refined levels of the dharma, there’s a clear distinction between what should and shouldn’t be done.

Which means that even though the Buddha taught metaphysical non-duality with regard to some issues, he didn’t take a blanket non-dual approach to all issues, and especially not to moral ones. The distinction between actions that should and shouldn’t be done is a duality that offers protection, inside and out, on every level of the practice, from the most basic to the most advanced.

If we look at the Buddha’s teachings on this duality in terms of Western psychoanalysis, we can see that what he’s teaching is a healthy super-ego, the functions of the mind that provide you with a strong sense of what should and shouldn’t be done. However, unlike the Western super-ego that Sigmund Freud studied, the Buddhist super-ego is not heedless of your happiness, and it’s not forced on you against your will. Instead, its primary concern is focused directly on your true happiness, and the Buddha offers his shoulds as conditional. He’s not demanding that you take on his shoulds, but from his vast experience he’s advising you that if you want true happiness, if you want to protect yourself, and if you want to end your bewilderment, this is how it has to be done. The choice to take on these shoulds—or not—is yours.

The sad irony is that the basic duality of the Buddha’s protective teachings has become so deeply obscured over the centuries. A teaching that the Buddha denounced—that the present moment is determined by your past kamma—has become widely accepted as the standard Buddhist explanation of kamma. Non-duality has been proclaimed as superior and more advanced than duality in all areas, including the distinction between right and wrong, what should and shouldn’t be done. The ego has been so demonized that many students are led to believe that all ego and super-ego functions have to be obliterated if they want to gain awakening.

The result is that many people who encounter these unsafe teachings when coming to Buddhism actually find themselves stripped of whatever protective sense of “should and shouldn’t be done” they might already have. This has led, as we’ve all too often seen, to their exploitation by unscrupulous teachers.

It would clearly be for the good of the world if the Buddha’s protective teachings were dusted off and returned to their rightful, central place in every school of practice that claims to take inspiration from him. This might not prevent the exploitation of students in all cases. After all, there will always be people, both students and teachers, who see rules as an incitement to rebel. But—unlike the blanket teachings of ego-destruction and the non-duality of right and wrong—the clear distinction between what should and shouldn’t be done would provide no room at all for justifying such bewildered and unsafe behavior as “compassionate” or “advanced.”

Further reading: Here’s another take on the duality of good and evil by eco-dharma pioneer David Loy, a look at the sexual abuse scandals in Buddhist communities, and an article by Thanissaro Bhikkhu on everything you wanted to know about karma but were afraid to ask.