Universal Laws

      Niven's Laws
         1. Never throw shit at an armed man.
            1a. Never stand next to someone who is throwing shit at an armed man.
         2. Never fire a laser at a mirror.
         3. Mother Nature doesn't care if you're having fun.
         4. Giving up freedom for security is beginning to look naive. (Note: this originally read "F × S = k", signifying that the product of freedom and security is a constant.)
         5. Psi and/or magical powers, if real, are nearly useless.
         6. It is easier to destroy than to create.
         7. Any damn fool can predict the past.
         8. History never repeats itself.
         9. Ethics change with technology.
         10. Anarchy is the least stable of political structures.
         11. There is a time and a place for tact.
         12. The ways of being human are bounded but infinite.
         13. When your life starts to look like a soap opera, it's time to change the channel.
         14. The only universal message in science fiction: There exist minds that think as well as you do, but differently.
         15.  : Niven's Corollary: The gene-tampered turkey you're talking to isn't necessarily one of them.
         16. Never waste calories.
         17. There is no cause so right that one cannot find a fool following it.
         18. No technique works if it isn't used.
         19. Not responsible for advice not taken.
         20. Think before you make the coward's choice. Old age is not for sissies.
         21. Never let a waiter escape.

      Clarke's Laws
         1. When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
         2. The only way of discovering the limits of the possible is to venture a little way past them into the impossible.
         3. Any sufficiently advanced technology is indistinguishable from magic.
         4. For every expert there is an equal and opposite expert.

      Niven's Inverse to Clarke's Third Law
         3a. Any sufficiently advanced magic is indistinguishable from technology.

      Asimov's Corollary to Clarke's First Law
         1a. When, however, the lay public rallies round an idea that is denounced by distinguished but elderly scientists and supports that idea with great fervor and emotion -- the distinguished but elderly scientists are then, after all, probably right.

courtesy of webmatter.de