#Feedback Why say the definition of some is "some but not many" and not "some but not most?" Didn't we just hear that many != most? Why implicitly equate them here?

Resolved!

Is there always a winner? E.g. Elephants feed just as much in the summer as they do in the winter.

Seems like a comparison. But no winner.

Why is #1 an argument? The supposed conclusion "I've decided to go ahead with the operation." is not a claim, it is a description of a decision. The supposed premise "With my current medical condition, there may not be another alternative..." does nothing to support the truth that this individual has, in fact, decided to go forward with the operation. The claim here is about the decision to undergo the operation. There is no claim that such a decision is the correct decision. I could see a question being posed like "Does the fact that the individual claims "With my current medical condition, there may not be another alternative..." strengthen or weaken the claim that undergoing the operation is the right decision, but this introduces a new claim that at the very best is only implied in the argument. As we saw from past lessons, implied premises (or conclusions) when not explicitly present, are not strictly part of the argument.

I think it's about looking at the purpose each of these statements have in the arguments presented. Yes, you could make an argument with the conclusion "Train service suffers when a railroad combines" but then again, you could also make an argument with the conclusion "When a railroad divides its attention between freight and commuter customers, it serves neither particularly well." If this were the conclusion, however, the other premises of the argument would have to support those conclusions. In this argument that is not how these statements are functioning. They are rather functioning as support for the final conclusion.

As far as question 2, I read the conclusion here being one about the strength of the evidence showing a lack of guilt not about the lack of guilt itself.

I don't think so. I would argue validity does not exist on a spectrum. The strength of an argument? Sure. But validity (taken in the video to be that the conclusion necessarily follows from the premises), either exists or it doesn't. Thus, the following argument having only three premises...

P1: Socks come only in red and blue

P2: The sock is not red

C1: Therefore the sock is blue

...is "valid" just like the Disney argument though containing fewer premises.

It seems the tiger argument could be transformed from a strong inference to a valid one with the addition of more premises, but not necessarily new non-implied information e.g.:

1. Not every mammal is suitable to keep as a pet.

2. Tigers are very aggressive and can cause serious injuries to people.

3. No animal that is very aggressive and can cause serious injuries to people is suitable to keep as a pet.

4. Tigers are mammals.

5. Therefore, not every mammal is suitable to keep as a pet.

This adds new information to the argument, but does not fundamentally alter its form. Further, you could say the explicitly added premises were implicit before giving the inference its strength.

However, it seems the same could not be done for the cat argument. Even if the cat "always" licks its paws after eating, there is no way one could draw a line of logical necessity between the actions of the cat after eating with the act of knocking over the trashcan without the addition of significant, non-implied information that alters the argument significantly. Even if the cat always licks its paws after eating, and this is the only time it licks its paws, there is no way to validly infer that it was the salmon in the trashcan, not any other food that caused the paw-licking or that it was the cat that knocked over the trashcan.

Assuming a conclusion is not wholly unsupported, is this a good litmus test between strong and weak support?