A difference of opinion is ...

A difference of opinion is what makes horse racing and missionaries.
A difference of opinion is what makes horse racing and missionaries.

Quotes from the same author

Good judgment comes from experience, and a lot of that comes from bad judgment.
If you find yourself in a hole, the first thing to do is stop digging.
Even if you're on the right track, you'll get run over if you just sit there.
You've got to go out on a limb sometimes because that's where the fruit is.
A man only learns by two things; one is reading and the other is association with smarter people.