Here’s the story behind Barney Stinson’s “one rule” in How I Met Your Mother. The character played by Neil Patrick Harris claimed to have one simple rule that he lived by. As revealed by the sitcom, Barney’s “one rule” turned out to be in fact, dozens of rules to live by. The topic was explained through a posting on Barney’s official blog.

Barney lived a very interesting lifestyle as showcased on the CBS sitcom. He developed a number of theories and ideologies stemming from his “Bro Code.” Many of Barney’s beliefs were focused on dating and his perception of women. He even developed a Playbook detailing a number of scams to win the affection of potential dates. Barney often tried to share his beliefs with his friends so they would eventually catch on with others, particularly Ted Mosby.

Unlike the majority of Barney’s mantras, his “one and only rule” centered on more than just his perception of women. The topic came up during the How I Met Your Mother season 6 episode, “A Change of Heart.” Barney tried to teach Ted a lesson about life and explained that he lives by “one rule” to guide himself through difficult situations. Ted pointed out that every time Barney said “I only have one rule…”, he followed it up with a completely different rule. The “one rule” line went on to become one of Barney’s major catchphrases considering the number of rules he ended up having.

Examples Of Barney’s “One Rule” From How I Met Your Mother

Barney detailed his “one and only rule” in an entry on his blog. In order for someone to discover their own “one rule,” they must commit it to memory even if that meant repeating it over and over again. Barney claimed that his strict morals were difficult to remember so it was key to never forget that “one rule.” In reality, Barney had over 40 rules which he considered his “one and only rule.” Here are Barney’s various “one rules”:

Barney did have one exception to his “one rule.” For every rule listed in his blog entry, Barney would bypass the statement if the woman in question was extremely attractive. In this case, Barney would add “…unless she’s hot” to the end of every rule to make it an exception in his eyes. Barney mentioned another “one and only rule” later in How I Met Your Mother season 6 in the episode “Challenge Accepted.” Barney told Ted that “new is always better” when referring to his architecture project. Ted once again pointed out that Barney’s rule kept changing but Barney argued that it was his oldest “one rule,” making it the best of all.

Never date a girl with a hook for a hand.

Never go out with a chick whose last name ends in a vowel.

If you’re gonna get it on in a portable toilet, do it early in the day.

Never meet a girl’s parents.

Never pass up a free sample.

Never pet a chicken.

If “Don’t Stop Believing” comes on, stop whatever you’re doing and sing along with one hand up in the air.

Never check a bag.

If it’s yellow, flush it down, too.

Never spell check.

Never trust a dude with hair past his shoulders.

Never trust a dude with hair ON his shoulders.

Never delete “Sex and the city” from your DVR.

Never enter a wine bar. They attract women over 30.

Never wear a brown belt with black shoes.

No cats.

Never take a girl back to your place, especially if your place is the White House.

Always wash your hands before returning to work.

Never leave home with less than three condoms in your wallet.

However old a girl says she is add five years. However much a girl says she weighs add twenty pounds.

Never make the first or third out at third base.

Never meet a girl for lunch.

Never repeat yourself.

Don’t say the same thing twice.

Bang twice, dump once.

The longer the line, the better the food.

Throw it high, say “goodbye.” Throw it low, you’re going to the show.

If you pay your taxes before a court mandates that you do, you’ve paid too soon.

When travelling internationally, it’s best to stick to bottled water and avoid ice cubes.

C-cups and up.

Never run without stretching.

Never wear a clip-on.

Never use an airplane lavatory.

Wait at least an hour after eating before humping.

He who smelt it, dealt it.

Ask yourself, “What would Ted do?” Then do the opposite.

Never order a “small” beer.

Black tie is never optional.

If someone yells “Duck!” then duck.

When a girl tells you how many guys she’s slept with multiply by three to get the real number.

You can tell how old a girl is by her elbows.

Flax seed relieves upset stomach.

Always have a fake pair of concert tickets in your pocket in case Lily invites you to something stupid.

Lebanese girls sprint to third base and then stay there.

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