Here's my first problem with
The Poison of Subjectivism. It comes pretty quick, in the 2nd sentence. (Coulda been worse, eh?

)
Correct thinking will not make good men of bad ones; but a purely theoretical error may remove ordinary checks to evil and deprive good intentions of their natural support.
Obviously, one must agree with Lewis on what "correct thinking" is. Which means one must agree with his worldview. As rus frequently states, not doing so is proof of incorrect (short-circuited/insane) thinking.
His own logic, hitherto the king whom events in all possible worlds must obey, becomes merely subjective. There is no reason for supposing that it yields truth.
There are a great many reasons for supposing logic yields truth. The understanding that each individual has of reality's laws is what allows each individual to remain alive. Logic says that, if a watermelon is seriously damaged when dropped from a fifth floor balcony,
I might be seriously damaged from the same drop. It would be illogical to test the theory, and most of us don't. In fact, the definition of "correct thinking" might be that thinking which does not make one act against the laws of reality that keep us alive.
Our logic
also allows us to make incredible technological advancements. The fact that our logic
does keep us alive and let's us make these advancements means that it
does work. And there is no reason to assume it will suddenly become inaccurate when examining itself.
There are modern scientists, I am told, who have dropped the words truth and reality out of their vocabulary and who hold that the end of their work is not to know what is there but simply to get practical results.
This is a very odd sentence. Science examines reality. Practical results are what allow us to understand reality. To discover facts, learn laws. To know what's there.
As I've said, I define "truth" and "fact" as different things. I'm not sure whether the scientific community agrees with me or not, which might make things difficult to discuss. But it keeps things clear for me. A fact is something we can see, define, test, retest, quantify, predict, etc. Truth is how we view the facts; how we fit them into our beliefs.
the fatal superstition that men can create values, that a community can choose its "ideology" as men choose their clothes.
Yes. This is exactly how the world has always worked. Different communities have had different values. Those values are what
define the community. Is the community one of freedom and equality? One of diversity? One of oppression? One of homogeneity? And each community makes rules that are designed to keep itself, to keep its defining values, alive.
Everyone is indignant when he hears the Germans define justice as that which is to the interest of the Third Reich. But it is not always remembered that this indignation is perfectly groundless if we ourselves regard morality as a subjective sentiment to be altered at will. Unless there is some objective standard of good, overarching Germans, Japanese, and ourselves alike whether any of us obey it or no, then of course the Germans are as competent to create their ideology as we are to create ours. If "good" and "better" are terms deriving their sole meaning from the ideology of each people, then of course ideologies themselves cannot be better or worse than one another. Unless the measuring rod is independent of the things measured, we can do no measuring.
The Nazi values are as correct for the Nazis as any other culture's is for them. Many other cultures and individuals are so appalled by the Nazis because their Nazis go so strongly against their own; not because the Nazis go so strongly against an objective standard. There have been and are enough other cultures that agree wholeheartedly with the Nazis in spirit, if not necessarily in specifics. (The Hutus thought that genocide was the answer to their problems with the Tutsis. Early America thought that genocide was the answer to its problems with the Indians. The Serbs thought that genocide was the answer to their problems with the Bosniaks. The Nazis, of course, would have, given the chance, killed everyone mentioned.) Simply put, it is up to each culture to try to ensure its own survival. Most other cultures opposed the Nazis, because the Nazis would have eradicated all other cultures. If I want to survive, I must stop you from killing me.
And, often enough, cultures are also attacked from within. For reasons
other than shared values, cultures often grow so big that they contain groups with values other than those that the culture is supposedly based on. A common enemy might unite people into what is seen as a single culture. But is India a single culture? Is the USA? Is New York State? No, none of them are. So the cultures - the groups that share values - within these entities are often at odds.
I've only brought up things within the first five paragraphs so far.

You can rebut as much as you want, rus, but I won't respond. There is no point. What point in "No, he is correct, because..." "No, he is wrong, because..." As I always say, this is putting the cart before the horse. One must first believe that God created us all a certain way before one will believe that we all feel the same moral law, which some then choose to act against. If one does not believe God created us all a certain way, one might think that the many different ways people behave are an indication that people
feel many different ways.