These rules are lifted from http://www.recguns.com/Sources/XIIIA4.html - they deserve all credit for them
III. Safety and Security
4. Jeff Cooper's Rules of Gun Safety
From Pages 8-10 of
The Modern Technique of the Pistol,
by Greg Morrison, Gunsite Press, Paulden, Arizona, ISBN 0-9621342-3-6, Library of Congress Number 91-72644, $40
RULE I: ALL GUNS ARE ALWAYS LOADED
There are no exceptions. Do not pretend that this is true. Some people and organizations take this rule and weaken it; e.g. "Treat all guns as if they were loaded." Unfortunately, the "as if" compromises the directness of the statement by implying that they are unloaded, but we will treat them as though they are loaded. No good! Safety rules must be worded forcefully so that they are never treated lightly or reduced to partial compliance.
All guns are always loaded - period!
This must be your mind-set. If someone hands you a firearm and says, "Don't worry, it's not loaded," you do not dare believe him. You need not be impolite, but check it yourself. Remember, there are no accidents, only negligent acts. Check it. Do not let yourself fall prey to a situation where you might feel compelled to squeal, "I didn't know it was loaded!"
RULE II: NEVER LET THE MUZZLE COVER ANYTHING YOU ARE NOT WILLING TO DESTROY
Conspicuously and continuously violated, especially with pistols, Rule II applies whether you are involved in range practice, daily carry, or examination. If the weapon is assembled and in someone's hands, it is capable of being discharged. A firearm holstered properly, lying on a table, or placed in a scabbard is of no danger to anyone. Only when handled is there a need for concern. This rule applies to fighting as well as to daily handling. If you are not willing to take a human life, do not cover a person with the muzzle. This rule also applies to your own person. Do not allow the muzzle to cover your extremities, e.g. using both hands to reholster the pistol. This practice is unsound, both procedurally and tactically. You may need a free hand for something important. Proper holster design should provide for one-handed holstering, so avoid holsters which collapse after withdrawing the pistol. (Note: It is dangerous to push the muzzle against the inside edge of the holster nearest the body to "open" it since this results in your pointing the pistol at your midsection.) Dry-practice in the home is a worthwhile habit and it will result in more deeply programmed reflexes. Most of the reflexes involved in the Modern Technique do not require that a shot be fired. Particular procedures for dry-firing in the home will be covered later. Let it suffice for now that you do not dry-fire using a "target" that you wish not to see destroyed. (Recall RULE I as well.)
RULE III: KEEP YOUR FINGER OFF THE TRIGGER UNTIL YOUR SIGHTS ARE ON THE TARGET
Rule III is violated most anytime the uneducated person handles a firearm. Whether on TV, in the theaters, or at the range, people seem fascinated with having their finger on the trigger. Never stand or walk around with your finger on the trigger. It is unprofessional, dangerous, and, perhaps most damaging to the psyche, it is klutzy looking. Never fire a shot unless the sights are superimposed on the target and you have made a conscious decision to fire. Firing an unaligned pistol in a fight gains nothing. If you believe that the defensive pistol is only an intimidation tool - not something to be used - carry blanks, or better yet, reevaluate having one around. If you are going to launch a projectile, it had best be directed purposely. Danger abounds if you allow your finger to dawdle inside the trigger guard. As soon as the sights leave the target, the trigger-finger leaves the trigger and straightens alongside the frame. Since the hand normally prefers to work as a unit - as in grasping - separating the function of the trigger-finger from the rest of the hand takes effort. The five-finger grasp is a deeply programmed reflex. Under sufficient stress, and with the finger already placed on the trigger, an unexpected movement, misstep or surprise could result in a negligent discharge. Speed cannot be gained from such a premature placement of the trigger-finger. Bringing the sights to bear on the target, whether from the holster or the Guard Position, takes more time than that required for moving the trigger finger an inch or so to the trigger.
RULE IV: BE SURE OF YOUR TARGET
Know what it is, what is in line with it, and what is behind it. Never shoot at anything you have not positively identified. Be aware of your surroundings, whether on the range or in a fight. Do not assume anything. Know what you are doing.
Make these rules a part of your character. Never compromise them. Improper gun handling results from ignorance and improper role modeling, such as handling your gun like your favorite actor does. Education can cure this. You can make a difference by following these gunhandling rules and insisting that those around you do the same. Set the example. Who knows what tragedies you, or someone you influence, may prevent?
(Thanks to David Post [email@example.com], who posted this extract to the news group)