#20 - Physicist: Determinism is the view that every event

[LSAT2018]

Would this be a Errors in the Use of Evidence, specifically that the lack of evidence for a position (in this case, the inability to be measure accurately) is taken to prove that position is false?

I didn't catch this at first because I thought there was inconsistency between measuring the position and velocity of particles with knowing the complete state of the universe. Something along the lines of Errors of Composition/Division as stated in answer (B). I thought there were two flaws in the stimulus, so given cases like this, how do I know which flaw to focus on?

[LSAT2018]

And I always tend to get lost in the details for common errors like this, especially when the answer choices are worded ambiguously. Any tips on how to improve on questions like these?

[Adam Tyson]

I think it's fair to view this one as a Lack of Evidence Flaw, LSAT2018, as you described - just because we don't know and cannot measure the complete state of the universe doesn't prove that there IS no such complete state. I think it's also okay to view this as a General Lack of Relevant Evidence Flaw - not knowing the state of the universe is irrelevant to there being such a state, and also to what that state may or may not cause (since the argument is about causes and not about knowledge).

Labels are helpful at times, but when we start striving to label the flaw precisely we can end up off track and coming up with a prephrase that is constricting rather than helpful. When you aren't sure what label to apply, don't try to apply one, but instead describe what is wrong in your own words. Maybe "just because you can't measure it doesn't mean it isn't there"? Or "just because we don't know what it is doesn't mean it isn't causing things to happen"? Then you can sort losers and contenders, eliminating answers that are obviously wrong (if any - sometimes they ALL look like contenders, which hurts!) and then either select the one that seems best or else guess and move on, living to fight another day (and perhaps to get the chance to come back to this one later and see if it is easier the second time around).

If you clearly see two distinct flaws, don't focus on just one of them, but take BOTH into the sorting process! Either could be a correct answer, so focusing on one to the exclusion of the other could seriously handicap you. Instead, sort the answers with the prephrase "it's one of these two flaws"!

Good luck, keep at it!

[silent7706]

Hi,

Can someone please explain why (D) is the right answer?

I was thinking along the line that “Just because it's impossible to measure position and velocity of any given subatomic particle, does not mean we cannot measure position and velocity of a collection of subatomic particles as a whole...”, leading me to zeroed in between (A) and (E). Although I felt both were the same, I ultimately picked (E).

It's clear that I missed the mark. Do you have any suggestions to avoid mistakes as such?

Thanks in advance.

[James Finch]

Hi Silent,

It looks like you mistook the flaw in the stimulus as a part-to whole problem. The issue I see in the stimulus is that the physicist is using attempting to use the inability to prove something as proof that it doesn't exist. Here, determinism cannot exist/be true because we as humans cannot possibly know two things--position and velocity of subatomic particles--at the same time. Does this inability to measure or know those two things mean that they aren't fixed or determined? Not necessarily, it only means that we can't know it or prove it. (D) sums this up well.

As for future questions, it always depends upon the specific flaw or flaws that exist in the stimulus. Be careful to understand exactly what is going on and always go for a prephrase with these question types before diving into the answer choices.

Hope this helps!