"Nature has placed mankind under the government of two sovereign masters, pain and pleasure...they govern us in all we do, in all we say, in all we think: every effort we can make to throw off our subjection, will serve but to demonstrate and confirm it." - Jeremy Bentham, [1748-1832]

"All substances are poisons: there is none which is not a poison. The right dose differentiates a poison and a remedy." - Paracelso, [1493-1541]