A Closer Look at the Old Tolerance
Under the older view of tolerance, a person might be judged tolerant if, while holding strong views, he or she insisted that others had the right to dissent from those views and argue their own cases. This view of tolerance is in line with the famous utterance often (if erroneously) assigned to Voltaire: “I disapprove of what you say, but I will defend to the death your right to say it.” This older view of tolerance makes three assumptions: (1) there is objective truth out there, and it is our duty to pursue that truth; (2) the various parties in a dispute think that they know what the truth of the matter is, even though they disagree sharply, each party thinking the other is wrong; (3) nevertheless they hold that the best chance of uncovering the truth of the matter, or the best chance of persuading most people with reason and not with coercion, is by the unhindered exchange of ideas, no matter how wrongheaded some of those ideas seem. This third assumption demands that all sides insist that their opponents must not be silenced or crushed. Free inquiry may eventually bring the truth out; it is likely to convince the greatest number of people.
The “Defeater Belief”
The fact that the new tolerance is most prone to label all of its opponents intolerant leads to a second reflection. The charge of intolerance has come to wield enormous power in much of Western culture – at least as much as the charge of “communist” during the McCarthy years. It functions as a “defeater belief.” A defeater belief is a belief that defeats other beliefs – i.e., if you hold a defeater belief to be true (whether it is true or not is irrelevant), you cannot possibly hold certain other beliefs to be true: the defeater belief rules certain other beliefs out of court and thus defeats them. For instance, if you believe that there is no one way to salvation and that those who think there is only one way to salvation are ignorant and intolerant, then voices that insist Islam is the only way, or that Jesus is the only way, will not be credible to you: you will dismiss their beliefs as ignorant and intolerant, nicely defeated by your own belief that there cannot possibly be only one way to salvation. Your belief has defeated theirs.
So if a Christian articulates a well-thought-out exposition of who Jesus is and what he has done, including how his cross and resurrection constitute the only way by which human beings can be reconciled to God, the person who holds the defeater belief I’ve just described may listen with some intellectual interest but readily dismiss everything you say without much thought. Put together several such defeater beliefs and make them widely popular, and you have created an implausibility structure: opposing beliefs are thought so implausible as to be scarcely worth listening to, let alone compelling or convincing. Put these last two reflections together and the scope of the challenge becomes daunting and alarming. The new tolerance tends to avoid serious engagement over difficult moral issues, analyzing almost every issue on the one axis tolerant/intolerant, excluding all others from the pantheon of the virtuous who do not align with this axis.
D. A. Carson. The Intolerance of Tolerance, 6-7, 15.