Even though boxing has been around for hundreds of years, few athletes have commanded as much respect and reverence as Jack Dempsey (1895-1983), the modestly-sized pugilist who toppled heavyweights far exceeding his 187 lb. fighting weight during his heyday in the 1920s.

In 1950, the same year the Associated Press named him Fighter of the Century, Dempsey published an instructional book titled Championship Fighting: Explosive Punching and Aggressive Defense [PDF]. In it, Dempsey holds court on his philosophies regarding self-defense for the layman and professional alike and stresses technique above all. While you’re probably better off getting one-on-one lessons in managing attacks, many of Dempsey’s tips remain valid today—so long as you can forgive some of his more curious metaphors. Here are 10 things Dempsey wanted you to know about the Sweet Science.

1. EVEN A BABY CAN KNOCK SOMEONE OUT—AND YOU ARE STRONGER THAN A BABY.

Championship Fighting insists that the reader understand the importance of putting one’s weight behind punches: Dempsey helpfully illustrates his point by having you consider how even a child can seriously injure an adult given the proper circumstances. “What would happen if a year-old baby fell from a fourth-floor window onto the head of a burly truck driver standing on the sidewalk?” he writes. “It's practically certain that the truckman would be knocked unconscious. He might die of brain concussion or a broken neck. Even an innocent little baby can become a dangerous missile when its body weight is set into fast motion.”

2. BEWARE OF BIG CROWDS; THEY LEAD TO CONFLICT.

A big portion of self-defense is situational awareness, and Dempsey cautions that large gatherings should be treated with a guarded attitude. According to Dempsey:

Populations increased so rapidly during the past quarter-century, while improved methods in transportation shrank the globe, that there is much crowding now. Also, the pace of living has been so stepped-up that there is much more tension in nearly every activity than there was in the old days. Crowding, pace, and tension cause friction, flare-ups, angry words and blows. That unprecedented friction can be noted particularly in cities, where tempers are shortened by traffic jams, sidewalk bumpings, crowdings in subways and on buses, and jostlings in theaters, saloons and nightclubs.

3. KNOW YOUR ENVIRONMENT.

Has a hooligan drawn you into a physical confrontation? Before you even think about raining blows upon him, consider your arena: “Let me suggest that any time you are about to be drawn into a fight, keep your head and make a split-second survey of your surroundings," Dempsey cautions. "Decide immediately whether you have fighting-room and whether you have good footing. If you haven't, try to force your opponent to shift to another battleground, where your knowledge of fighting will leave the percentage in your favor. Yell at him, for example: ‘Okay, wise guy! You want to fight! Let's see if you've got the guts to come out into the street and fight me like a man!’”

This, Dempsey says, will allow you to avoid obstacles and crowds, “so that you'll be able to knock his head off when you get him where you can fight without footing handicaps.”

4. YOU NEED TO STUMBLE BEFORE YOU CAN FIGHT.

Dempsey had a very specific method for generating some of the forward momentum needed to land a devastating strike on the jaw, mouth, or nose of your instigator: Imagine yourself stumbling forward. “It is a quick, convulsive and extremely awkward step,” he writes. “Yet, it's one of the most important steps of your fistic life; for that falling-forward lurch is the rough diamond out of which will be ground the beautiful, straight knockout jolt. It's the gem-movement of straight punching. Try that falling step many times.”

5. YOUR PINKY IS THE KEY TO YOUR POWER.

Those new to inflicting violence might not stop to consider where power comes from and how it’s transferred. Dempsey discusses this by having amateurs refer to their shoulder and then “draw” a straight line all the way down to the pinky finger. “The power line runs from either shoulder straight down the length of the arm to the fist knuckle of the little finger, when the fist is doubled. Remember: The power line ends in the fist knuckle of the little finger on either hand," Dempsey writes. "Gaze upon your ‘pinky’ with new respect. You might call that pinky knuckle the exit of your power line- the muzzle of your cannon."

6. USE THE ”SNEAKER” PUNCH.

The former champ is exhaustive in his study of the numerous weapons available to boxers, from the left hook to the snot-box-crushing uppercut. But he reserves the most affection for what he calls the “sneaker punch,” a blow dealt over your opponent’s arms after a break in the clinch.

“In boxing, it is illegal for you to use this blow, or any other, after the referee has told you to break. But you can use it before he orders a break—when you make your own break. In fist-fighting you can use it whenever you get the chance.”

Dempsey’s description:

(1) Keep your head in close to the left side of your opponent's head, with your chin slightly over his shoulder. (2) Maneuver with your left hand until you can grab the inside crook of his right elbow, and thus hold his right arm so firmly that he can't punch with it. (3) Get his left arm under your right arm, and clamp your right hand under his arm—just above the elbow—just below the biceps. When you hold him in that fashion, he can't hit you; but you are in perfect position to break away sharply and deliver a stunning overhanded "sneaker" hook.

7. NEVER SWING, UNLESS YOU WANT A RIDE IN A HEARSE.

Any pro will tell you that straight punches are the key to victory: Wild, looping punches dilute your guard and lack precision. Dempsey is no different. “Some current fighters attempt a long-range right upper-cut called the ‘bolo’ punch. They even attempt to lead with it. Let me warn you that the bolo is more showy than explosive. It's more dangerous to the user than to his opponent. The bolo, or any long-range uppercut, is merely an underhanded swing. And you know that any type of swing, against a good straight puncher, signals to the mortician.”

8. WATCH YOUR OPPONENT’S WRISTS.

To help anticipate your opponent’s moves, Dempsey advocates keeping watch on the position of his or her wrists. On a related note, he advises not to close your eyes while being punched. “Never close your eyes; no matter what kind of a punch is coming at you, and no matter what kind of a punch you are throwing. Keep your eyes riveted on his left fist. After you develop the habit of watching punches, you'll discover that even though your eyes are focused on one threatening fist, you'll be noting from the corners of your eyes every other move your opponent is making.”

9. DON'T COUNT YOURSELF OUT BECAUSE OF YOUR SIZE.

Although he advocates routine fitness programs, Dempsey doesn’t subscribe to the theory that you need to be a chiseled beefcake in order to protect yourself. “Though you resemble a circus fat man or a human skeleton, you'll be able to fight surprisingly well if you practice the fundamentals of explosive fighting I've explained in this book. You'll be able to stiffen many a fellow with one punch, or with a couple of punches.”

10. FINISH IT QUICK.

The number one obstacle to victory in any altercation, Dempsey writes, is fatigue. “True, your opponent also may be getting fatigued; but you can't be certain about his exact condition unless he's blowing and staggering. You know for sure only that you're nearly ‘all in,’ and that he's still out there swinging at you. Accordingly, the longer he keeps fighting, the less chance you have of winning; but the greater chance you have of being battered, cut up, knocked down, knocked out, or injured.”

The “Manassa Mauler” has practical advice to combat this issue. “Because of the danger in a fist-fight, it is imperative that you end the brawl as quickly as possible; and the best way to do that is by a knockout. The knockout is far more important in fist-fighting than in boxing, YOU'VE GOT TO KNOCK 'EM OUT IN FIST-FIGHTS.”

If a baby can do it, so can you.