@MajorTom it is only until i read your comment that i finally, clearly saw the difference between only, and the only in this context. THANK YOU!

i fell for the oldest trick in the book. BUT NEVER AGAIN

@HadiSyed that's great!! and yeah, practice makes for faster applications of technique! keep it up :)

this one took me a little bit trying to rely on intuition but then after realizing i could diagram this in my head it became clear using De Morgan's law

buy -> confident of authenticity and find the piece desirable

contrapositive:

/find the piece desirable OR /confident -> /buy

(E) simply fulfills one of the sufficient conditions (can't be confident of the authenticity) and therefore should not buy it. it doesn't matter if she also likes the vase.

@RQuaye37 i did the same. the conclusions were easy enough to come to, but i think the purpose of this exercise is to prepare us to find conclusions that are a little more occluded

@jaydenca because it doesn't change the meaning. they are both necessary and sufficient for each other so it doesn't matter if we flip them or not, so, to simplify, we just don't flip (is what i would assume)

i was feeling pretty defeated about using lawgic yesterday, but then i got this question right in 1min32sec using EXACTLY what ive learned about lawgic in the previous sections, and its given me new life lol.

5/5 taking an average of just under 1min30sec to finish each question. im making progress and it feels great!

@AdriJ thanks for this. it really helped put this into perspective

it was almost like magic using lawgic to solve this. wow