Sufficient vs Necessary

cpedolzky

I feel like i have been getting these confused. Could someone explain the approach to solving these? I know the NA has to be true but what does that even mean I think im overthinking these questions.

nicholas.leon96

NA must be true for the argument to hold any water at all, SA makes the argument valid. NA are usually very weak compared to SA, things that you might take for granted.

Example of NA:
If the weather is good tomorrow, we will catch lot of fish at the lake
The weather will be good tomorrow
Therefore, we will catch lots of fish
A necessary assumption here would be that there are even fish in the lake to begin with! Something so subtle that you could honestly pretty reasonably assume to be true without it being stated out right.

Whereas SA questions are something that makes the conclusion valid. I like to think about it as we have conclusion Y, we need to find answer choice X that works as a sufficient assumption to trigger the conclusion, in other words X->Y where X is the answer choice and Y is the conclusion in the stimulus.

Example:
The weather will be good tomorrow
We will catch lots of fish tomorrow
Sufficient assumption: if the weather is good tomorrow, we will catch lots of fish

I hope this helps!

Ben Udeze

Great Explanation!