Posting on Behalf of a 7Sage User: 4 Groups Mixed Translations Flashcards

Theo - Student Service

[I am posting on behalf of a 7Sage user. Please feel free to leave your comments below. Thank you for your help!]

"From 4 Groups Mixed Translations Flashcards, I've been stuck on two problems and I think it comes from a lack of understanding of how Group 3 and Group 4 work.

Not both /S and O is /S -> /O. I intuitively understand this but I don't understand how the rules make this happen. Same goes for None of the M is /D being M -> D. Shouldn't it be /M -> D?

I couldn't find any replies covering this."

https://7sage.com/lesson/4-groups-mixed-translations-flashcards/

Herk Driver

"Not both" and "none" are both Group 4.

Let's start with "Not both /S and O".

The process for Group 4 is:

1) Pick either idea. [I'll pick '/S' as the idea]
2) Negate that idea. [/S becomes S]
3) Make that idea the necessary condition. [ -----> S]
4) The other idea is the sufficient condition. [O ---- > S ]
Thus we get O ---> S with /S ---> /O as the contrapositive.

+++++++++++++++++++++++++++++++++++++++

Now "none". "None of the M is /D"

1) Pick either idea. [M]
2) Negate that idea. [/M]
3) Make that idea the necessary condition. [ -----> /M]
4) The other idea is the sufficient condition. [/D ---- > /M ]
Thus we get /D ---> /M with M ---> D as the contrapositive.

Hope that helps!