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.

Resolved!

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?

#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?