Suppose that you and I have different sets of beliefs. You believe the world is M-wise. I believe it is O-wise. Suppose you happily engage in conversations with me about how O the world is. You do this even though you believe the world only has M properties. You are tolerant.
One would think that such a model successfully describes, at least, one way of being tolerant. It is simple and clear. Nonetheless, it is also misleading.
Suppose that M is intelligent design theory, while O is evolution theory. They are inconsistent, if just because O presupposes that there is no intelligent designer. Now suppose that you happily agree to discuss how evolutionary-like the world is, even though you actually believe it is more like intelligently designed. That’s supposed to make you tolerant.
If you are attracted by that way of thinking, you will be deceived. As a matter of fact, there are tons of M-people that will happily engage in conversations concerning the evolutionary properties of the world that would, nonetheless, happily kill someone who dares to attack their religious beliefs. That does not make them tolerant.
I think it is advisable to distinguish among, at least, two forms of tolerance: a superficial, conversational, tolerance; and a deep, critical form of it. Both will happily engage in conversations about opposing, and even inconsistent, views. However, it is only the latter that will be so disposed as to consider the possibility of being mistaken. Conversational tolerance goes easy (and even some dare to miss it). I think it is superficial. Argumentative tolerance, however, requires something more: the almost unattainable ability to disbelief oneself within reasonable limits.
If this is true, then we have an explanation of some interesting phenomenon. Statistically speaking, the overwhelming (capital ‘O’) majority (i.e., 90% or so) of the residents of Mexico prove to be religious (more specifically, catholic). The numbers are less embarrassing in the US. However, educated audiences in the US (i.e., undergraduates) prove to be way less tolerant of criticisms of intelligent design than their counterparts in Mexico. Why is it so?
Well, suppose there are, at least, two forms of tolerance: conversational and argumentative. Educated audiences in Mexico prove to be conversationally tolerant, whereas their US counterparts do not. Does this prove that they are also argumentatively tolerant? I would not be so sure. Rather, I would think that their presupposition (i.e., that intelligent-design is true) is so deeply assumed that it becomes impenetrable. They can happily engage in conversations that would otherwise (i.e., if they were critical about it) undermine their assumptions.
At the end of the day, conversational tolerance may prove to be superficial and, perhaps, worthless.