Context

The first line gives away the ending: the speaker is saying that crazy people are sane and sane people are crazy.

Hello, paradox.

The speaker doesn't pull any punches with this first line; she gets right to the point and jabs it in our face. She's not necessarily saying that those whom society stamps as insane are smart and sensible in a practical way; instead, the speaker describes their version of smarts as "divinest." Godlike, maybe? They might forget to put pants on before they leave the house, but they have a direct line to what's going on in the larger Universe.

Many of Dickinson's poems deal with her love/hate relationship with God and religion as a whole, so it's no big surprise to see the theme pop up here. 

Oh, and you might notice Emily using one of her favorite tricks: capitalizing words for emphasis. Both Madness and Sense are capitalized, making each word seem bigger somehow. Capitalized, these words could represent all madness and all sense.

Where you've heard it

Emily Dickinson isn't the only author who thought that madness wasn't as simple as it seemed. Here are a few others:

• Alda Merini
• Sylvia Plath
• Allen Ginsberg
• Ken Kesey

Pretentious Factor

If you were to drop this quote at a dinner party, would you get an in-unison "awww" or would everyone roll their eyes and never invite you back? Here it is, on a scale of 1-10.

Speaking in poetry is a little weird, but we kind of like the sentiment.