Sin is sweet in the beginning, but bitter in the end.
The Talmud in Wikipedia
My scientific studies have afforded me great gratification; and I am convinced that it will not be long before the whole world acknowledges the results of my work.
(July 20, 1822 - January 06, 1884)
Men have never been good, they are not good and they never will be good
(May 10, 1886 - December 10, 1968)
What worries you, masters you.