Blood money.

In a thoroughly depressing conversation yesterday, a nice woman expressed her admiration for my (our) fortitude. "You artists have so much to work against," she said. 

"You must do it for love," she continued.

You got it, lady. 

Illustration=love. Another easy formula.

Altho, money would be a close second.

Illustration=love=money. The formula is getting a little more advanced but you can't go on if you don't grasp it.

Now pass me another Bloody Mary.