In the first scene of act four of Henry V, the English army face a near-impossible situation: They're sick, outnumbered, and isolated. And they face a battle against the entire army of France. The king greets two of his advisors, Gloucester and Bedford, with the following:

Gloucester, 'tis true that we are in great danger;

The greater therefore should our courage be.

Good morrow, brother Bedford. God Almighty!

There is some soul of goodness in things evil,

Would men observingly distil it out.

For our bad neighbour makes us early stirrers,

Which is both healthful and good husbandry:

Besides, they are our outward consciences,

And preachers to us all, admonishing

That we should dress us fairly for our end.

Thus may we gather honey from the weed,

And make a moral of the devil himself.

The character of Henry V is a matter of considerable contention, and I myself have had conflicting opinions about him. (I'll be writing about some of them soon.) But these matters are beside today's point. It is the words and ideas that must be thought about, and the ones above are remarkable. At the center of the king's argument is an astonishing idea - that people and situations that we dislike are not only to be endured, they are necessary. The Beatles may have been partially wrong: We need love, certainly, but we may need its opposite as well, because many undertakings and accomplishments arise from what we normally term the negative emotions. What a thought is contained in lines 8 to 10! Our enemies function as "our outward consciences" and we make decisions to do our best in order to prove them wrong. Perhaps this concept can help to explain why people will divide themselves into factions for almost any reason. (Kurt Vonnegut once said that if religion, race and nationality weren't available, people would divide into groups based on the first letters in their names.) But seeing the biggest picture possible - which the greatest writers can help us to do - perhaps these divisions have "a soul of goodness" in them.