Wadler's Blog

A penny saved is a penny earned./You have to spend money to make money.
 

It seems that there is a proverb for every (generally two) outcome of most common situations, and none of them is truer than the other. They shouldn't be used as arguments in themselves, only to underline others.

Although birds of a feather flock together, you can't judge a book by its cover.
 

One of the classical Biblical instances of this is Proverbs 26:4-5:

Do not answer a fool according to his folly,
or you yourself will be just like him.

Answer a fool according to his folly,
or he will be wise in his own eyes.

Although, in this case, I think the point of the Proverb pair is more to say you just can't win when talking to some people.
 

... I don't mean to offend, but this particular observation has been made since the dawn of human civilization. How can you claim you are proposing it, without giving due credit to --- for example --- http://www.google.com/search?&q=opposite proverb blog?
 

Birds of a feather flock together.

- vs -

Opposites attract.
 

Absence makes the heart grow fonder. / Out of sight, out of mind.
 

Too many cooks spoil the broth.
Many hands make light work.
 

Do "Do unto others as you would have them do unto you" have an opposite?
 

Niels Bohr: "The opposite of a correct statement is a false statement. But the opposite of a profound truth may well be another profound truth."
 

Look before you leap ... but he who hesitates is lost.

(Best said with a slight pause between the clauses, to a person poised on the precipice.)
 

An eye for an eye. / Turn the other cheek.