Necessary vs. Sufficient?

In sum, the sufficient condition (a.k.a. the "if" direction) allows you to get what you want. That is, if you assume the sufficient condition, you'll obtain your desired conclusion. It's enough. It's sufficient. 

On the other hand, the necessary condition (a.k.a. the "only if" direction) is the one you must assume in order to get what you want. In other words, if you don't have the necessary condition then you can't reach your desired conclusion. It is necessary

Here's a little graphic which summarizes this:


Related Posts

Four Flavors of Continuity

The Back Pocket

Comparing Topologies

The Back Pocket

"Up to Isomorphism"?

The Back Pocket

One Unspoken Rule of Algebra

The Back Pocket
Leave a comment!