Rule 1: justified only if the computer is typically used in the operation of a business.

Now consider two conclusions: access is justified versus access if not justified. Which conclusion is reachable via the first rule? Access is not justified. That is a reachable conclusion. To reach it, we just need to trigger the rule contrapositively. In other words, we need a premise establishing that the computer is not typically used in the operation of a business. The conclusion that access is justified is unreachable via this rule.

I got this question right but you have lost me entirely here. How is justified an unreachable conclusion via this rule. How is it not

Computer typically used in business -> Justified

Instead we're contrapositing the rule??? I genuinely don't understand. Is it just because of the grammar that we are interpreting the original rule as

Justified -> computer typically used in business

and turning it into

/computer typically used in business -> /justified

I just don't understand how using rule 1 we cant reach the conclusion that someone is justified. Especially when it says "One is justified if X".

Is this just sufficiency, necessity again? -_-

@DanielleMeuret You're my hero. This has been bugging the shit out of me.

@tswalker83 Reading the question stem first is really the key for these I think, in terms of time. By the time you're done reading the first author, you should likely be able to infer what the second author will disagree with, allowing you to read the second author with the focus of understanding the specific point theyre disagreeing with. When you finish the second author, you should be able to put in your own words what they disagree with and then just hunt for the answer that matches.

Don't watch videos like this in Dark Mode, it gives you an inverted color jump scare