I hope you don’t mind me pointing out logical flaws - I understand it can come across as patronising and some people find it difficult. Not my intention.
Your coloured additions unfortunately introduce another one to premise 2:
If we separate P2 by its logical conjunction (the “and”) into the subject “Humans” with two different predicates “condition OUGHT_ness from IS” and “derive OUGHT_ness from IS”, we note the latter predicate is equivalent to the conclusion.
(Humans) “derive OUGHT_ness from IS” is semantically identical to “OUGHT is derived from IS”. This is known as “begging the question”, which just means “assuming the conclusion” - i.e. a kind of circular reasoning where the conclusion is already in the premises. This is an informal logical fallacy - because of course your conclusion will follow from the premises if you’ve already stated it in a premise from which your conclusion is derived.
Deriving “ought” from “is”, and “ought” derived from is", use the active and passive voice respectively to mean the same thing - as I brought up in my last post.
I don’t want you to misunderstand me - using either voice is entirely valid grammatically: “being conditioned” is indeed grammatically correct, and so is (humans) “deriving ought from is”. The only thing that’s different is the “point of view”, if you like.
“The dog followed the human” and “the human was followed by the dog” describe identical situations, only the former (active voice in this case) is the point of the view of the dog, and the latter (passive voice in this case) is the point of view of the human. The dog is doing an action in the former, and the human is passively involved in what the dog’s doing in the latter, but the two statements are logically interchangeable as the semantic value carried by either voicing is identical.
As a suggestion: try to make the voices you’re using consistent throughout your argument if that helps you more easily assess the validity of its progression, because I think grammar is tripping you up here.
For your P1, you have the element “IS” being part of the set “things that are conditioned by humans”. This is fairly tautologous, because the property of existence is a pre-condition for being acted on in any way (e.g. being conditioned (by humans)).
For your P2, you state that “humans condition oughtness” as a fact, which seems fine to me.
If your conclusion is to be that “ought is derived from is”, perhaps it’s first necessary to establish that “conditioning” amounts to the object of conditioning being “derived” from the subject doing the conditioning. This would allow P2 to state that “oughtness is derived from humans”, or “humans derive oughtness” (same thing, different voice).
In this case, for P2 to validly lead to C1, P1 would have to be something like “humans are derived from IS_ness”. This would allow the form:
P1: B <= A
P2: C <= B
C1: C <= A
where A denotes “IS_ness”, B denotes “humans”, and C denotes “OUGHT_ness”. I wrote the arrows backwards to mimic the passive voice that makes the argument easier to read:
“Humans” derived from “is”, ought derived from “humans”, therefore “ought” derived from “is”.
And I guess humans are indeed derived from “IS_ness”, given objective existence independent of the human perception of it - as most people believe it to be.
But as sound as this syllogism now is, all it really says is that “ought” is a thing that exists that comes to existence via the existence of humans. This seems fairly uncontroversial.
“You can’t get an is from an ought” is getting at something different. “Ought” is an element of the set “Is”, because oughtness “exists”. But there is nothing necessarily “ought” as a result of what “is”.
It’s possible to assert an ought “within” the scope of what “is”, about something that “is”, as something that “is”. This invokes the realm of modal logic:
P1: “Is” possibly derives humans (A → ◇B)
P2: Humans possibly derive oughts (◇B → ◇C)
C1: It is possible that “is” derives “ought”, but it is not necessary that “is” derives “ought”. (A → ◇C ∧ ¬:white_medium_square:C)
Basically, you can derive “ought” from “is”, but to do is is arbitrary and unjustified by virtue of any necessity. So unfortunately it’s not pseudo-science that justifies moral relativism, it’s logic.