Conditional Logic: If vs. If and Only If

chefmmmmmm

Hi all,

I'm struggling a little with understanding how some of the conditional indicators (if, when, etc.) imply the exclusion of other conditions.

For example, the below makes sense to me:

If you are in New York, then you are in the United States.

Maybe because the content is familiar? Of course not being in the United States means you're not in New York, so /USA -> /NY

But, in the following example question:

A teacher earns respect if she fosters a love of learning.

Must we assume that if means if and only if, in this case meaning the only way she can earn respect is by fostering a love of learning? Couldn't she be a Nobel Prize winner that does not foster a love of learning, but is still respected?

gabraham196

Hey Chefmm,

So for conditional statements never take the sufficient condition as the ONLY way a necessary condition can happen. Let me explain via you're example.

If she fosters a love of learning -> earns respect
/earns respect -> /foster a love of learning

All we know here is that hey if she doesn't earn respect she can't foster a love of learning. WHY? because if she did foster of a love of learning that would mean she earned respect.

Yes you are right you can NOT foster love of learning and still earn respect. WHY because there could be other sufficient conditions for making earning respect.

Now don't ASSUME something not stated. If they want to say two conditions always happen together they will say it. If a statement says

IF and Only if she fosters a love will she earn respect = then yes both will always happen together.

If they say other things like "otherwise" then the same applies they always happen together.

(I would get an easier example and always use that if you're confused, this scenario is pretty tricky to bring up and remember when studying or doing a question) JY has a lesson where he gives some examples of conditional statements which could help you.

Also if you haven't studied LG there's some lessons in there which could help you better grasp conditionals, (when conditional rules trigger and fall away)

A sufficient condition just lets us know something happens.
But it could be very likely that a sufficient condition doesn't happen and that necessary condition still occurs

chefmmmmmm

THANK YOU! that helps!