The reason why E is wrong is because even if we concede that there is always a "risk" of iatrogenic disease, the argument is only making its conclusion within a world in which all iatrogenic disease has been prevented. So regardless, no one in this hypothetical world would die from iatrogenic disease anyways.

Our task in this question is to expose a flaw that would weaken the conclusion. So how does considering E to be true do anything to damage the claim that half of all deaths would be prevented? It doesn't.

I'm having trouble figuring out whether or not the stimulus is setting up a biconditional. When reading the second sentence, at the surface it sounds like critical thinking is necessary for and also guarantees protection against political demagogues. Additionally, it seems that if an orderly system of government is sufficient for critical thinking, then perhaps D could be true. Am I missing something?

I personally don't understand this explanation— B seems like it would be correct for a sufficient assumption question, but not a necessary assumption. Even if the preschooler's paintings were horribly ugly, there is a chance that the expressionist paintings were still objectively aesthetically pleasing. Obviously, B would be sufficient to ensure that the expressionist paintings are objectively pleasing, but it is not necessary.

Can someone please explain why the conclusion is the last sentence instead of "parents should be given additional votes"? I think I am used to automatically seeing prescriptive statements as conclusions, and it seems that the idea that "families with underage children would receive fair representation" is acting in support of this prescriptive statement. What am I missing here?

With conditional causal logic, I like to conceptualize it as drinking alcohol and hangovers.

hangover (effect) → drinking alcohol (necessary cause)

/drinking alcohol → /hangover

If someone told you that they didn't have a hangover this morning, would you automatically conclude they didn't touch alcohol last night? Obviously not. I had a liver of steel as a college student and simply did not get hangovers.

Similarly, if I told you that I drank alcohol, you cannot conclude that I will definitively experience a hangover.

Now let's look at sufficient causes.

drinking a handle of vodka (sufficient cause) → alcohol poisoning (effect)

Makes sense, right? Now unless you're superhuman, if you did NOT go to the ER then you can logically conclude that you did NOT drink an entire handle of vodka.

/alcohol poisoning → /drinking a handle of vodka

I can see that some people, including myself, are struggling to understand why D is wrong. In my view, I think it's because if we assumed D to be true, we are left with two disjointed facts: 1) trespassers caused damage and 2) Sandstrom knew this could happen. How are we supposed to logically infer that these two facts add up to "she should pay for damages"?

I feel like he made the explanation of A unnecessarily complicated— to me, the most glaring error is that if the researchers captured and measured only the small-beaked birds at the end of the study, they would have also done so at the beginning of the study. Therefore, they were still probably observing the same population of birds over the three decades, so A isn't accounting for the decrease in beak size that occurred.

Remember that the stimulus never actually compares the beak size between the wild and captive bird populations, just the change in beak size within each population.

I love hearing J.Y.'s political commentary on these questions. I feel safe here

I think the most important point about B is that it is not engaging with the reasoning structure at all— I knew going into this question that the correct answer would somehow contradict or weaken the results of the study, which seemingly pointed to computer programs being more accurate. Even though B is enticing, it does nothing to reconcile the results of the study.

I had a lot of trouble understanding why C is wrong but this is what I came up with: we can't make this claim because the legislator never even looked for evidence of opposition or support for the bill. Instead, they used polling data about the issue of taxation at large, which overwhelmingly pointed at opposition to high taxes. Therefore, our job is to expose why this data is not sufficient to indicate support for a bill as stated.

Another reason why D is wrong— the premises already explicitly state that most friendships began because someone felt comfortable approaching a stranger. So not only is D descriptively inaccurate, it is trying to deny one of the premises.

Like he said in an earlier video, we are trying to find a flaw in the reasoning between the premise and conclusion, and simply denying a premise is usually how we are expected to weaken the overall support relationship.