Sufficient and necessary terminology
Started by
Kenny
· started 2015-09-07 18:46
· last activity 2015-09-09 18:42
· 1 reply
The video explanation said that "everyone", "no one" and "none" are sufficient and necessary terms, however looking at the old videos, I can't determine whether they introduce a sufficient or necessary.
-
Naz
· 2015-09-09 18:42
Remember that the most important thing with Sufficient & Necessary is not to blindly follow rules and to take everything in context. With that said, more often then not, the words you indicated introduce sufficient conditions. However it gets trickier with the "none" and "no one" due to the negation.
Let's look at some examples:
(1) Everyone of A is B.
So this means: If A, then B.
A ==> B
not B ==> not A
(2) No one that has A will have B.
So this means: If A, then not B.
A ==> not B
B ==> not A
(3) None of A is B.
So this means: If A, then not B.
A ==> not B
B ==> not A
Hope that helps! Please let us know if you have any other questions.
Sign in to reply.