Sometimes, yes, but only along certain dimensions. If your group performs rituals, they can’t be rational because then they will be the same as other groups’. For example, the Jewish practice of eating flat bread on Passover is arbitrary [1], but it only works because it is arbitrary.
[1] It’s not entirely arbitrary if you believe the story of Passover, but that’s a somewhat different point. Actually, it may be interesting to examine whether it’s rational in that case—I can see arguments for both sides.
Interestingly, group rituals purely for the sake of group bonding needn’t be irrational. It’s irrational to believe that God is going to punish you if you eat leavened bread during Passover—I am caricacturizing Jewish theology here but the general point is sound—but it can be useful to set a test for group membership, or an action to marks you as part of a group, to help group cohesion. This is particularly useful if you’re up against other groups that would like to exploit you and you need as much help as possible to stay together so your group can put up a united front. Arbitrary dietary restrictions seem like a decent way to do that.
Not that anyone actually sat down and thought it out like this before deciding that Jews should abstain from leavened bread for a week every spring, or that Mormons shouldn’t drink alchohol, and so on. But I think there’s value in having an arbitrary ritual explicitly for the sake of group cohesion.
Sometimes, yes, but only along certain dimensions. If your group performs rituals, they can’t be rational because then they will be the same as other groups’. For example, the Jewish practice of eating flat bread on Passover is arbitrary [1], but it only works because it is arbitrary.
[1] It’s not entirely arbitrary if you believe the story of Passover, but that’s a somewhat different point. Actually, it may be interesting to examine whether it’s rational in that case—I can see arguments for both sides.
Interestingly, group rituals purely for the sake of group bonding needn’t be irrational. It’s irrational to believe that God is going to punish you if you eat leavened bread during Passover—I am caricacturizing Jewish theology here but the general point is sound—but it can be useful to set a test for group membership, or an action to marks you as part of a group, to help group cohesion. This is particularly useful if you’re up against other groups that would like to exploit you and you need as much help as possible to stay together so your group can put up a united front. Arbitrary dietary restrictions seem like a decent way to do that.
Not that anyone actually sat down and thought it out like this before deciding that Jews should abstain from leavened bread for a week every spring, or that Mormons shouldn’t drink alchohol, and so on. But I think there’s value in having an arbitrary ritual explicitly for the sake of group cohesion.