People will always work harder if they're getting well paid and if they're afraid of losing a job which they know will be hard to equal. As is well known, if you pay peanuts, you get monkeys.

Always pay; for first or last you must pay your entire debt.

In nature nothing can be given, all things are sold.

In every work a reward added makes the pleasure twice as great.

He that payeth beforehand shall have his work ill done.

"There are bullfighters who do it just for the money-they are worthless [said Hemingway]. The only one who matters is the bullfighter who feels it, so that if he did it for nothing, he would do it just as well. Same holds true for damn near everyone."

One pays for everything, the trick is not to pay too much of anything for anything.