Important Suff/Nec questions !! HELP! :) Forum

[nosleeptillsuccess]

Okay I know the basics of Suff/Nec conditions.. my questions here are...

1.)What's the rules for counter example?? I think it's suff without nec..

2.)On assumptions questions we are looking for necessary condition that links the premise to conclusion... right? and on justify conclusions we are searching for suff...right?

(I'm aware of negation technique on necessary assumption questions)

3. Any other "somewhat" challenging rules of suff/nec that are easy to forget that may apply to certain questions...


THANKS

[ws81086n]

Not sure what you mean by #1 or #3, but for #2, assumption questions sometimes ask for necessary assumptions, other times for sufficient assumptions. The question stem will make this clear. When the stem says something about the assumption being "required", or anything else than denotes necessity, you're looking for a necessary assumption. When it doesn't, and says the assumption will make the conclusion follow logically, you're looking for a sufficient assumption. A sufficient assumption can be the answer to a justify question, but the great majority of the time the stem will say "most justify", from which it follows that you're not necessarily/not likely to have a sufficient assumption as the answer.