The early days of the holiday season have brought into sharp relief a deeply disturbing trend that seems innocent enough at first glance, but in fact is the genesis of much that ails humanity. I speak of asymmetrical expectations borne from the destructive belief that one faith has more validity than another. Oddly, this pernicious impact of religion is seen most clearly during the secular holiday of Thanksgiving.

Through the miracle of marriage, one part of my extended family keeps a kosher home, and this plays an important part in the story to unfold. What does kosher mean? Reaching back to the archaic ways of nomadic tribes and rituals dating thousands of years, kashrut describes a body of Jewish laws that proscribe certain foods, explain what foods must be separated, and detail how certain foods must be prepared. Kosher can be used as a synonym for kashrut, but is more often used more restrictively to mean the foods (rather than the laws regulating those foods) that meet the standards for consumption and ritual use.

Kosher is not only broadly and badly misunderstood by non-Jews, but by the Jewish community as well. Ask any of your Jewish friends why kosher laws were developed, and almost all will say to promote better health. This is the biggest and most annoying myth of all, that kosher laws are some kind of primitive health code. The idea is complete nonsense. Yes, the methods described by kosher slaughter are sanitary, and were ahead of their times. But kosher laws are not driven by or a consequence of health concerns. Camel and rabbit are no less healthy than cow or goat. Having a cloven hoof does not make an animal healthier to eat than one that is not so endowed. And grape products, like wine, made by non-Jews are not in any way distinguishable from Jewish wines from a health perspective. Just compare a Manischewitz to a Rothschild.

The prohibition against eating meat with dairy is also entirely arbitrary, with no associated health benefit. Perhaps gulping down a huge glass of milk after eating an 18-ounce prime rib would interfere with digestion, but a little dab of butter used in basting a turkey would not. Some rabbis prohibit the consumption of turkey altogether, while others do not, because the poor bird was unknown to the authors of the Torah. The symbol of Thanksgiving remains permanently in kosher limbo.

Kosher laws are not health laws, and they are completely and utterly arbitrary. The only reason why Jews observe kosher law is because the Torah says to, and for no other reason. The Torah is perfectly silent on why the laws are promulgated. Not once does the Torah explain the chosen from the forbidden; never does the Torah state why a falcon drumstick is prohibited but a duck breast is OK with God.

The other prominent myth is that kosher and Jewish are synonymous. Not true by a wide margin. Keeping kosher is a choice, and not a popular one at that. At most, only 15 percent of American Jews observe kosher law. The inverse means that 85 percent of American Jews believe that keeping kosher is irrelevant to being a good, pious Jew. Let us be clear: The vast majority of American Jews are no more kosher than the Catholic priest down the street.

And so now we come to Thanksgiving dinner, hosted by my extended family. Non-Jews, kosher Jews, and non-kosher Jews all converge onto the tableau of a Norman Rockwell painting for the quintessential American celebration. The fireplace glows with a warm heat while guests gather around, drinks in one hand, nosh in the other. The din of happy conversation mutes the flurry of last-minute instructions escaping from the kitchen.  But trouble is brewing beneath the oil-painted veneer of family bliss.

With disparate religious beliefs coming together to break bread, who and what will prevail? Not all practices are compatible. The host proudly cooks a turkey in the tradition of her great-great grandmother, who used butter liberally in all preparations. Combining dairy and meat is prohibited in the eyes of the kosher guests. Houston, we have a problem.

This problem actually began a few weeks earlier when my niece called to request that her aunt prepare a kosher Thanksgiving dinner. Kosher always trumps all other belief systems in the eyes of an observant kosher Jew. My niece not only requested but also expected her aunt to throw out generations of family tradition to accommodate her beliefs.

What is wrong with that picture? The asymmetry. If the situation were reversed and my niece were hosting the dinner, her aunt would not call and request or expect my niece to prepare a meal to her specifications. So when a kosher Jew is a guest, the host is expected to provide kosher food, but when the kosher Jew is a host, the guest is expected to eat kosher food; it is all kosher all the time in all circumstances. Kosher trumps no matter what. The inherent arrogance of that is astonishing, but no more so than the manner in which the unidirectional bias is broadly seen as acceptable in our society.

Before going further, let us eliminate some trivial objections to the developing thread of my argument. I agree that a good host always attempts to accommodate the needs of a guest. But that obvious retort is meaningless here because of the asymmetry; my niece would not accommodate her aunt in my niece’s home if doing so violated some kosher law.

We can also eliminate from this discussion dietary restrictions due to health concerns. Obviously, we would not want to serve peanuts to somebody with a severe allergy to that legume. We would not serve beef to somebody with an adverse reaction to red meat. Causing anaphylactic shock in a guest is generally considered undesirable. These examples do not apply in any way to a discussion of kosher law either; kosher is a religious restriction, not a dietary one. Kosher is a choice, while allergies are not.

What about voluntary vegetarians who choose to avoid red meat for ethical rather than medical reasons? Like being kosher, vegetarianism is a choice, and therefore subject to the same arguments concerning accommodation. I suspect there might be a difference between asking a host to accommodate a lifestyle choice and imposing your religious laws on another, but the distinction if it exists is awfully subtle. One belief system should not trump another. Mutual respect implies symmetry in execution.

Finally, let us eliminate the easy way out: just avoid those who share different beliefs. After all, my niece could have simply declined the invitation to Thanksgiving dinner at her aunt’s house and spent the evening with another Jewish family serving a kosher meal. But that is a baby-with-bathwater solution, avoiding rather than confronting and solving the problem. That approach also implies a certain arrogance, the very kind we are trying to avoid: “If you want to see me, you have to serve food my way; if not, hasta la vista.” My way or the highway.

Now we can return to the issue in play. On one hand, this Thanksgiving episode can easily be dismissed as a trite domestic tiff with no interest beyond the walls of the aunt’s house. On the other hand, ignoring the broader lesson would be a terrible mistake: The asymmetrical expectation revealed in my niece’s demand based on her religious beliefs is a microcosm of what is wrong with much of the world. What is so terribly frightening is how easily we accept such asymmetries because of our best qualities: We fear offending, just want to get along, want to be gracious and accommodating, wish others to be happy. Why argue? I’ll accommodate you even though I know you will not accommodate me. I’ll be the bigger person. It is not big deal.

Yes. It. Is. Tolerating asymmetry in small samples and in personal interactions enables the disease of asymmetrical expectations to spread globally, with disastrous consequences.

From any dispassionate perspective, my niece’s request to change the meal plan is outrageous. But we pretend otherwise, offering the excuse that she must follow her faith, ignoring the hidden evil that she expects all others to follow hers. That is religion’s worst characteristic: the arrogance of false conviction, that my faith is more valid than yours, my rituals are more important than yours, and that if we have to choose between the two, we’ll do mine.

Of course, I believe that kosher is a silly anachronism derived from ignorant nomadic tribes, with no place in this century. Still, when I’m in somebody else’s home, I have no problem complying with the host’s customs—whether it’s kosher needs or saying grace before a meal. But I would then expect that person as a guest in my house to comply with my customs (like eating the meal without saying grace). I would happily accommodate a friend’s customs and needs at my house—if I knew she would do the same for me in hers. But not if my beliefs are always subservient to hers. That type of asymmetry is treacherous, and should not be accepted.

Mixing religion with the asymmetrical expectation that one faith has more validity or priority than another is a primary cause of many, perhaps most, conflicts in human history. Since religion is based on faith rather than facts, no mechanism exists to arbitrate between competing ideas. Is the idea that Jesus rose from the dead any more or less silly than the notion that Joseph Smith was led by angels to golden plates in New York? As soon as logic is removed from the debate, competing positions cannot be evaluated based on relative merit, but are supported as inherently right, immune to any reasonable counterarguments. Without logic, nobody has any basis on which to conclude that one faith has a greater claim to legitimacy than another. There is no way to assign the label of truth to one system of belief among many. The only way to support a position is simply to assert supremacy as loudly as possible, since no objective facts are available to evaluate any particular claim. We are reduced to tantrums of “I’m right, you’re wrong, I win.” And if each faith has the asymmetrical belief that it is the one and true, and no way to prove that claim other than by fiat, the result is a fight of the faiths.

Tolerance requires symmetry. I accept your beliefs as valid for you, and you accept my beliefs as valid for me. Tolerance can only exist in an atmosphere of reciprocity. As soon as asymmetrical expectations enter the stage, tolerance is impossible. When unidirectional, tolerance is nothing but submission and acquiescence. The asymmetrical expectations derived from faith are wrong and dangerous. By accepting these asymmetries, we are not being nice; we are enabling the worst of our human characteristics.