A fuller quote is just above. here I focus on
This is where two philosophies clash. The one says yes, these are equivalent 'beliefs' which have been equally scorned. There is no difference between factual truth and professed faith; the conviction that the genocide took place and the certitude that Muhammad was illuminated by Archangel Gabriel are on a par. The others say no, the reality of the death camps is a matter of historical fact, whereas the sacredness of the prophets is a matter of personal belief.
In this passage Glucksman is presenting the standard western view on the fact value distinction, which he calls the truth belief distinction. His view is very conventional in English speaking countries and somewhat more likely to be challenged in France where a slightly larger fraction of academics deny that there are objective facts. Eager to write something eccentric, and sincerely believing what I write, I disagree completely.
I consider five words four of which are decent English "belief", "truth", "fact", "knowledge" and "verifiable." To me a fact is a truth and vice versa. I recognise that the word fact is the English translation of the past partiple of the generic latin transitive verb and therefore once meant "event" something that happened at a specific place and a specific time. I don't care about etymology. Now we can say that the law of conservation of momentum is a fact and be correct if it is a true statement about the world. To me a belief is a state of mind which is true if it corresponds to external reality and is false if it doesn't. So I see no foom for belief which is neither true nor false. Finally knowledge is justified true belief where the key word is "justified". I think beliefs can only be justified within a system of thought so there can not be objective knowledge. I do think that there can be objective truth (sad to say this is to say I believe in ontological objectivity but not in epistemelogical objectivity). Glucksman identifies "truth" with "verifiable truth" asserting that there is no unknowable truth.
This might sound logical, however it is inconsistent with mathematical logic. If one accepts that there is such a thing as mathematical truth (I don't know if Glucksman does) and the it can only be verified by proofs, then there are unknowable truths. This is Goedel's theorem and it has been proven. One kind of unknowable truth is the answer to a question of the form "does this polynomial have a root which is a rational number." Sounds pretty well defined no ?
Now back to Glucksman's example, do I think that "the conviction that the genocide took place and the certitude that Muhammad was illuminated by Archangel Gabriel are on a par." I do in the sense that I think that the belief that the genocide took place and the belief that Muhammad was illuminated by Archangel Gabriel are roughly similar cognitive entities. I think they differ, because one is a true belief and the other is a false belief, but each are claims about objective reality.
Now no Moslem is going to prefer Glucksman's version to mine. The idea that belief in Allah is just a feeling and not a claim which is true of false is, I think, just as offensive as the idea that it is a false claim. Glucksman will not say that the difference is that his belief is true and moslem's beliefs are false. So he invents a catagory of beliefs which are neither true nor false to dodge the question.
Now it is clear that we both agree that there can be passionately felt beliefs which do not correspond to anything outside the believer. I call them false beliefs. There is no doubt in my mind that Glucksman is personally certain that Gabriel did not illuminate Muhammad (in fact I assume that he is an atheist like me). I think he has learned the dodge of creating a category for religious beliefs which makes it possible to call them "valid" while believing that they do not correspond to reality.
Now I ask Glucksman how he feels about another possible statement. How about "the holocaust was wrong" According to Glucksman this is not a statement of fact. A claim about what is right and what is wrong is clearly a statement of values, hence for Glucksman a matter of belief not truth. Now, given his argument with the moslems, does Glucksman think it would be OK to deny the statement "the holocaust was wrong"?
I am very reluctant to perform the operation even as a hypothetical, but what if someone were to say "the holocaust was the right thing to do. Let's finish the job."
Would Glucksman consider that covered by free speech. It is not a verifiable assertion. No historian or scientist can prove that something was morally wrong. The statement is illegal in France. How about wearing a swastika ? That is not a statement which can be proven false, because it isn't an assertion. Is that covered by free speach ? Not in Germany where it is illegal.
The claim that Europe is determined to tollerate any expression which can not be proven false by looking at the facts is simply false. Glucksman has responded to one specific accusation that Europe is not really committed to freedom of speech but he must know perfectly well that his argument is false and absurd. He manages to respond only by leaving out the inconvenient fact that many laws in Europe which ban speech on matters which are not scientifically verifiable.
OK how about me. What is my possition on "the holocaust was wrong". I think it is a true statement, just plain true. I recognise that neither logic nor evidence can be used to prove that something was morally wrong. I don't consider proof necessary for me to believe something. I think my unprovable belief that the holocaust was wrong is objectively true.