I'm not sure about this one, and I'm having a very tough time seeing why the correct answer is correct.
Link: http://classic.7sage.com/lsat_explanations/lsat-35-section-4-question-11/
One way to approach the question "what is real?" is to say that something is real IF AND ONLY IF that thing is posited by the most explanatory powerful theory of the science. Most scientific theories have things posited as real only on theoretical grounds. Therefore, the approach described is flawed.
What I am looking for: This is PSA question, so we need to link up the premise to the conclusion. If something is posited as real only on theoretical grounds, then it isn't a part of the most explanatory powerful theory. That's what I anticipated, but I'm not that confident about it.
Answer A: We don't care about enhancing a theory.
Answer B: This is the correct answer, but I don't really see what it's doing. Doesn't this answer choice assume that there is an overlap between the "most explanatory powerful theory of the science" and "most scientific theories contain only theoretically posited entities?" Why couldn't the "most explanatory powerful theory of the science" be in the group of non-theoretically posited entities (i.e. only in the group of practically posited entities?) That doesn't seem like an unreasonable assumption.
Answer C: I think this is kind of like answer A. We don't care about enhancement of a theory.
Answer D: OK, but this doesn't seem like a sufficient assumption. Plus, are the entities real?
Answer E: I don't think this is it because the author thinks this reasoning is flawed, so this doesn't seem like a sufficient assumption.


