The original bon mot was from Pablo Picasso. A guy in a restaurant asked him to make a quick sketch on a paper napkin. Picasso draw it. The guy asked him to sign it. Picasso said "OK, but then you'll give me 500 francs " (it probably was a bargain at the time...) "-500 francs? but it took you just a second!""-no,it may not seem so, but actually it took me 60 years".