Let's take this slowly:
Harris alludes to Hume's is/ought problem in his talk and he also mentions it explicitly in the book. Does anyone disagree with this?
Although he mentions it, Harris does not solve the is/ought problem in either the book or the talk, therefore the problem still stands. Does anyone disagree with this?
Note that in the book, Harris mentions Hume and is/ought, but then goes along to address G.E. Moore's Open Question argument. He ducks out of the confrontation with Hume. Does anyone disagree with this?
If the is/ought problem stands, then science (what is) cannot determine human values (what ought to be). It simply can't. Facts and values are forever separated, until we assume a non-scientific premise (as Sam Harris admits that he does with his ‘well-being’ assumption). Does anyone disagree with this? Harris seems to disagree with this. He says things like:
I am going to argue that the separation of facts and values is an illusion.
Yet facts and values are separated and Hume explains exactly how they are separated, which is why he is germane to the discussion. If Harris had argued that facts and values are not separated if first we assume other things to be true, then I would not have an issue with him. Yet he never makes this crystal clear, preferring instead the headline-grabbing statements such as the one above and the one included in the subtitle of his book.
The strongest reference Harris makes to is/ought is from one of his rebuttals. Harris writes:
Many of my critics piously cite Hume’s is/ought distinction as though it were well known to be the last word on the subject of morality until the end of time. Indeed, Carroll appears to think that Hume’s lazy analysis of facts and values is so compelling that he elevates it to the status of mathematical truth:
Note that Harris does not refute Hume anywhere at anytime. Yet here he describes Hume's analysis of facts (is statements) and values (ought statements) as 'lazy'. Note that this is critical of Hume without exactly saying whether he is right or wrong. Unfortunately, I now feel compelled to call this criticism, 'lazy' for what it is:
a weasel word. It gives the impression that Hume’s analysis is deficient, but as anyone who knows Hume will understand, Hume’s observation about is/ought is either refuted or it stands. It is not a matter of Hume not having the energy to solve it. No one has solved it including Harris. Calling it ‘lazy’ makes no sense and does not address the problem in any meaningful way. I would suggest that it is a criticism that verges on stupidity.
Also, Harris seems to fundamentally misunderstand his critics. Yes Harris makes a lot of other arguments in the book and the talk, but until he honestly addresses Hume these criticisms involving is/ought will not go away. It would be simple for Harris to say:
‘No, you’ve all got the wrong end of the stick, I haven’t refuted Hume, I am not claiming that I have, I’m sorry for the confusion.’
Then most of his critics would disappear in a puff of smoke.
Yet we are left with a kind of confusion about whether Harris believes he has solved is/ought or not. Does anyone disagree with this?
Given all this, I think that Harris could halt a lot of confusion by answering whether he believes Hume is right or wrong in his observation (for that is what it is) about is/ought statements and if he believes Hume is wrong, how exactly is Hume wrong. The fact that given copious opportunities he does not address this issue is telling. Is it because:
If the is/ought problem stands, then science (what is) cannot determine human values (what ought to be)?
Also, one final point: given that Sam Harris has written a work of moral philosophy and that solving the is/ought problem would be a groundbreaking event in moral philosophy and that Sam Harrris repeatedly alludes to is/ought and is critical of is/ought (Hume's lazy analysis); then it is therefore quite right for philosophers and those interested in moral philosophy to pick him up on this point, demonstrate that he hasn't solved it and demand some clarification as to whether he thinks he has solved it. Does anyone disagree with this?