Imannuel Kant – universal law

“Act according to a maxim which can, at the same time, be valid as a universal law.—You must, therefore begin by looking at the subjective principle of your action. But to know whether this principle is also objectively valid, your reason must subject it to the test of conceiving yourself as giving universal law through this principle. If your maxim qualifies for a giving of universal law, then it qualifies as objectively valid.” ~Imannuel Kant