First, it must be established that the stimulus sets up an 'If and Only If' relationship between the following conditions:
"A scientific theory is a good theory if it satisfies.”
AND
"It must accurately describe
The combination of the “IF” and the “MUST” allows us to conclude that this is an “If and only if” conditional. I have no problem with this part of the stimulus. My problem is with the word “Few” in the second condition.
"Few" is a relative term. I don't see how it has any logical boundaries with the exception of "one or more". Answer choice D states that "A scientific theory that contains many elements is not a good theory." "Many" is also a relative term. However, for the purposes of the LSAT, I believe people have been debating whether "Many" means "one or more" or "more than two". If we accept the former definition, then there is really no way to rule out answer choice D, because "Few" and "Many" would have the same strict logical boundaries and would therefore be interchangeable in this context.
Since the question stem asks for what must be true EXCEPT (i.e. what is not necessarily true), the incorrect answer choices MUST BE TRUE. However, I submit that based on the former definition of “Many”, which is “one or more”, the statement in Answer choice D is not necessarily true and therefore could be the correct answer. A scientific theory that contains “MANY” elements could contain as many as “FEW” elements (one) based on the previously discussed definition. If this were the case, then we could not deduce that the model was not a good theory until knowing whether or not the other half of that condition had been met.
Based on this, we can deduce that one of the following probably happened:
1.) The LSAC screwed up. This is only PT4.
2.) “Many” actually means “two or more” for the purposes of the LSAT; or
3.) The LSAC intended “Many” to be relative to “Few” within the context of this passage. In any event, I think this would be a writing error.
Can anyone check my work here?