Problems that go away by themselves, come back by themselves.
If you have to travel on a Titanic, why not go first class?
Variables won't, constants aren't.
If it's green or wiggles, it's biology. If it stinks, it's chemistry. If it doesn't work, it's physics.
An infallible method of conciliating a tiger is to allow oneself to be devoured.
Money isn't everything. It isn't plentiful, for instance.
A word to the wise is superfluous.
A milligram of prevention is worth a kilogram of cure.
A bird in the hand is inconvenient.
If at first you don't succeed, you've got one strike against you.