Original Murphy's law

If there are two or more ways to do something, and one of those ways can result in a catastrophe, then someone will do it.

Murphy's laws (modern version)

• If anything can go wrong, it will.
• If there is a possibility of several things going wrong, the one that will cause the most damage will be the first one to go wrong.
• If anything just cannot go wrong, it will anyway.
• If you perceive that there are four possible ways in which something can go wrong and circumvent these, then a fifth way, unprepared for, will promptly develop.
• Left to themselves, things tend to go from bad to worse.
• If everything seems to be going well, you have obviously overlooked something.
• Nature always sides with the hidden flaw.
• Mother Nature is a bitch.

In Nature, nothing is ever right, therefore if everything is going right something has to be wrong.

Forsyth's second corollary to Murphy's laws.

Just when you see the light at the end of the tunnel, the roof caves in.

Zymurg's seventh exception to Murphy's law

When it rains, it pours.

O'Toole's commentary on Murphy's laws.

Murphy was an optimist.

Comment on Murphy's Law

Murphy's Law is recursive. Washing your car to make it rain doesn't work.

Chisolm's First Corollary to Murphy's Second Law

When things just can't possibly get any worse, they will.

Finagle's Laws of Dynamic Negatives

• Anything that can go wrong, will.
• The perversity of the Universe tends towards a maximum.

Finagle's fourth law

Once a job is fouled up, anything made to improve it will make it worse.

Hanlon's Razor

Never attribute to malice that which can be adequately explained by stupidity.

Ginsberg's theorems.

1. You can't win.
2. You can't break even.
3. You can't even quit the game.

Weiler's law

Nothing is impossible to the man who doesn't have to do it himself.

Gumperson's law

The probability of anything happening is in inverse ratio to it's desirability.

Law of the Perversity of Nature

You cannot successfully determine beforehand which side of the bread to butter.

Jenning's Corollary

The chance of the bread falling with the buttered side down is directly proportional to the cost of the carpet.

Lazlo's Chinese Relativity Axiom

No matter how great your triumphs or how tragic your defeats -- approximately one billion Chinese couldn't care less.

## Lois specifiques a l'informatique et aux sciences

Parkinson's Law of Data

Data expands to fill the space available for storage.

The laws of computer programming.

• Any given program, when running, is obsolete.
• Any given program costs more and takes longer each time it is run.
• If a program is useful it will have to be changed.
• If a program is useless it will have to be documented.
• Any given program will expand to fill all the available memory.
• The value of a program is inversely proportional to the weight of it's output.
• Program complexity grows until it exceeds the capability of the programmer who is supposed to maintain it.

Golub's laws of computerdom.

• Fuzzy project objectives are used to avoid embarrassment of estimating the corresponding costs.
• A carelessly planned project takes three times longer to complete than expected. A carefully planned project only takes twice as long.
• The effort required to correct course increase geometrically with time.
• Project teams detest weekly progress reportings because it so vividly manifests their lack of progress.

Pierce's law.

In any computer system, the machine will always misinterpret, misconstrue, misprint or not evaluate any math or subroutines or fail to print any output on at least the first run through.

Corollary to Pierce's law

When a compiler accepts a program without error on the first run, the program will not yield the desired output.

Brook's Law

If at first you don't succeed, transform your data set !

Grosch's law

Computing power increases as the square of the cost.

Osborn's law

Variables won't be, constants never are.

Gilb's laws of unreliability

• Computers are unreliable but humans are even more unreliable.
• Any system that depends on human reliability is unreliable.
• Undetectable errors are infinite in variety; in contrast to detectable errors, which by definition are limited.
• Investment in reliability will increase until it exceeds the probable cost of errors, or until someone insists on getting some useful work done.

Lubarsky's law of cybernetic entomology

There's always one more bug.

Troutman's postulates

• Profanity is the one language understood by all programmers.
• Not until a program has been in production for six months will the most harmful error be discovered.
• Job control cards that positively cannot be arranged in improper order will be.
• Interchangeable tapes won't be.
• If the input editor has been designed to reject all bad input, an ingenious idiot will discover a method to get bad data past it.
• If a test installation works perfectly, all subsequent systems will malfunction.

Weinberger's second law

If builders built buildings the way programmers wrote programs, the first woodpecker that came along would destroy civilisation.

Gummidge's law

The amount of expertise varies in inverse ratio to the number of statements understood by the general public.

Harvard's law, as applied to computers

Under the most rigorously controlled conditions of pressure, temperature, humidity and other variables, the computer does as it damn well pleases.

Sattinger's law

It works better if you plug it in.

Jenkinson's law

It won't work.

Horner's five thumb postulate

Experience varies directly with equipment ruined.

Cheop's law

Nothing ever gets built on schedule or within budget.

Rule of accuracy

When working towards the solution of a problem it always helps if you know the answer

Pudder's laws

• Anything that begins well ends badly.
• Anything that begins badly ends up worse.

Westhimer's rule

To estimate the time it takes to do a task, estimate the time you thing it should take, multiply by two and change to the next highest unit. Thus we allocate two days for a one hour task.

Stockmayer's theorem

If it looks easy, it's tough. If it looks tough it's damn near impossible.

Brooke's law

Adding manpower to a late software only makes it later.

Featherkile's rule

Whatever you did, say that's what you planned.

Flap's law

Any inanimate object, regardless of it's position, configuration or purpose, may be expected to perform at any time in a totally unexpected manner for reasons that are either totally obscure or else completely mysterious.

Anthony's Law of Force

Don't force it; get a larger hammer.

Anthony's Law of the Workshop

Any tool when dropped, will roll into the least accessible corner of the workshop.

Corollary to Anthony's Law of the Workshop

On the way to the corner, any dropped tool will first strike your toes.

Arnold's Laws of Documentation

• If it should exist, it doesn't.
• If it does exist, it's out of date.
• Only documentation for useless programs transcends the first two laws.

Boob's Law

You always find something in the last place you look.

Boren's Laws

• When in charge, ponder.
• When in trouble, delegate.
• When in doubt, mumble.

Brady's First Law of Problem Solving

When confronted by a difficult problem, you can solve it more easily by reducing it to the question, "How would the Lone Ranger have handled this?"

Brooke's Law

Whenever a system becomes completely defined, some damn fool discovers something which either abolishes the system or expands it beyond recognition.

Chism's Law of Completion

The amount of time required to complete a government project is precisely equal to the length of time already spent on it.

Conway's Law

In any organization there will always be one person who knows what is going on. This person must be fired.

Finagle's Creed

Science is true. Don't be misled by facts.

Finagle's First Law

If an experiment works, something has gone wrong.

Finagle's fourth Law

Once a job is fouled up, anything done to improve it only makes it worse.

Finagle's Second Law

No matter what the anticipated result, there will always be someone eager to (a) misinterpret it, (b) fake it, or (c) believe it happened according to his own pet theory.

Finagle's Third Law

In any collection of data, the figure most obviously correct, beyond all need of checking, is the mistake

Corollaries to Finagle's Third Law

Nobody whom you ask for help will see it. The first person who stops by, whose advice you really don't want to hear, will see it immediately.

Flon's Law

There is not now, and never will be, a language in which it is the least bit difficult to write bad programs.

Fudd's First Law of Opposition

Push something hard enough and it will fall over.

Gerrold's Laws of Infernal Dynamics

• An object in motion will always be headed in the wrong direction.
• An object at rest will always be in the wrong place.
• The energy required to change either one of these states will always be more than you wish to expend, but never so much as to make the task totally impossible.

The Briggs/Chase Law of Program Development

To determine how long it will take to write and debug a program, take your best estimate, multiply that by two, add one, and convert to the next higher time unit.

Gray's Law of Programming

`n+1' trivial tasks are expected to be accomplished in the same time as `n' tasks.

Logg's Rebuttal to Gray's Law

H. L. Mencken's Law

Those who can -- do. Those who can't -- teach.

Martin's Extension to H. L. Mencken's Law

Those who cannot teach -- administrate.

Hacker's Law

The belief that enhanced understanding will necessarily stir a nation to action is one of mankind's oldest illusions.

If you have a difficult task, give it to a lazy person -- they will find an easier way to do it.

Hoare's Law of Large Problems

Inside every large problem is a small problem struggling to get out.

It always takes longer than you expect, even when you take Hofstadter's Law into account.

Johnson's First Law

When any mechanical contrivance fails, it will do so at the most inconvenient possible time.

Jone's Law

The man who smiles when things go wrong has thought of someone to blame it on.

Jones's First Law

Anyone who makes a significant contribution to any field of endeavor, and stays in that field long enough, becomes an obstruction to its progress -- in direct proportion to the importance of their original contribution.

Katz' Law

Man and nations will act rationally when all other possibilities have been exhausted.

Kinkler's Second Law

All the easy problems have been solved.

Lackland's Laws

1. Never be first.
2. Never be last.
3. Never volunteer for anything

Langsam's Laws

• Everything depends.
• Nothing is always.
• Everything is sometimes.

Larkinson's Law

All laws are basically false.

Law of Communications

The inevitable result of improved and enlarged communications between different levels in a hierarchy is a vastly increased area of misunderstanding.

Law of Probable Dispersal

Whatever it is that hits the fan will not be evenly distributed.

Law of Selective Gravity

An object will fall so as to do the most damage.

Laws of Serendipity

• In order to discover anything, you must be looking for something.
• If you wish to make an improved product, you must already be engaged in making an inferior one.

Turnaucka's Law

The attention span of a computer is only as long as its electrical cord.

Velilind's Laws of Experimentation

• If reproducibility may be a problem, conduct the test only once.
• If a straight line fit is required, obtain only two data points.

### Autres lois...

Leibowitz's Rule

When hammering a nail, you will never hit your finger if you hold the hammer with both hands.

Lewis's Law of Travel

The first piece of luggage out of the chute doesn't belong to anyone, ever.

Lieberman's Law

Everybody lies, but it doesn't matter since nobody listens.

Lowery's Law

If it jams -- force it. If it breaks, it needed replacing anyway.

Maier's Law

If the facts do not conform to the theory, they must be disposed of.

Corollaries to Maier's Law

• The bigger the theory, the better.
• The experiment may be considered a success if no more than 50% of the observed measurements must be discarded to obtain a correspondence with the theory.

Maintainer's Motto

If we can't fix it, it ain't broke.

Malek's Law

Any simple idea will be worded in the most complicated way.

Whatever happens to you, it will previously have happened to everyone you know, only more so.

Meskimen's Law

There's never time to do it right, but there's always time to do it over.

Miksch's Law

If a string has one end, then it has another end.

Mitchell's Law of Committees

Any simple problem can be made insoluble if enough meetings are held to discuss it.

Mosher's Law of Software Engineering

Don't worry if it doesn't work right. If everything did, you'd be out of a job.

Murphy's Law of Research

Enough research will tend to support your theory.

Naeser's Law

You can make it foolproof, but you can't make it damnfoolproof.

Newton's Fourth Law

Every action has an equal and opposite satisfaction.

Newton's Little-Known Seventh Law

A bird in the hand is safer than one overhead.

Non-Reciprocal Laws of Expectations

Negative expectations yield negative results. Positive expectations yield negative results.

Ogden's Law

The sooner you fall behind, the more time you have to catch up.

Oliver's Law

Experience is something you don't get until just after you need it.

Ozman's Laws

• If someone says he will do something "without fail," he won't.
• The more people talk on the phone, the less money they make.
• People who go to conferences are the ones who shouldn't.
• Pizza always burns the roof of your mouth.

Parker's Law

Beauty is only skin deep, but ugly goes clean to the bone.

Parkinson's Fifth Law

If there is a way to delay in important decision, the good bureaucracy, public or private, will find it.

Parkinson's Fourth Law

The number of people in any working group tends to increase regardless of the amount of work to be done.

Paul's Law

You can't fall off the floor.

Peter's Law of Substitution

Look after the molehills, and the mountains will look after themselves.

Pohl's law

Nothing is so good that somebody, somewhere, will not hate it.

Rhode's Law

When any principle, law, tenet, probability, happening, circumstance, or result can in no way be directly, indirectly, empirically, or circuitously proven, derived, implied, inferred, induced, deducted, estimated, or scientifically guessed, it will always for the purpose of convenience, expediency, political advantage, material gain, or personal comfort, or any combination of the above, or none of the above, be unilaterally and unequivocally assumed, proclaimed, and adhered to as absolute truth to be undeniably, universally, immutably, and infinitely so, until such time as it becomes advantageous to assume otherwise, maybe.

Rocky's Lemma of Innovation Prevention

Unless the results are known in advance, funding agencies will reject the proposal.

Rudin's Law

If there is a wrong way to do something, most people will do it every time.

Sattinger's Law

It works better if you plug it in.

Scott's first Law

No matter what goes wrong, it will probably look right.

Scott's second Law

When an error has been detected and corrected, it will be found to have been wrong in the first place.

Corollary

After the correction has been found in error, it will be impossible to fit the original quantity back into the equation.

If there are two possible ways to spell a person's name, you will pick the wrong one.

Corollary

If there is only one way to spell a name, you will spell it wrong, anyway.

Silverman's Law

If Murphy's Law can go wrong, it will.

Simon's Law

Everything put together falls apart sooner or later.

Sodd's Second Law

Sooner or later, the worst possible set of circumstances is bound to occur.

The three laws of thermodynamics

1. You can't get anything without working for it.
2. The most you can accomplish by working is to break even.
3. You can only break even at absolute zero.

Tussman's Law

Nothing is as inevitable as a mistake whose time has come.

Unnamed Law

If it happens, it must be possible.

Watson's Law

The reliability of machinery is inversely proportional to the number and significance of any persons watching it.

Weinberg's First Law

Progress is made on alternate Fridays.

Weinberg's Principle

An expert is a person who avoids the small errors while sweeping on to the grand fallacy.

Weiner's Law of Libraries

There are no answers, only cross references.

Westheimer's Discovery

A couple of months in the laboratory can frequently save a couple of hours in the library.

Wethern's Law

Assumption is the mother of all screw-ups.

Whistler's Law

You never know who is right, but you always know who is in charge.

Williams and Holland's Law

If enough data is collected, anything may be proven by statistical methods.

Zymurgy's Law of Volunteer Labor

People are always available for work in the past tense.

## D'autres lois qui n'ont vraiment rien à voir

The two constant Laws of Frisbee

1. The most powerful force in the world is that of a disc straining to land under a car, just out of reach (this force is technically termed "car suck").
2. Never precede any maneuver by a comment more predictive than "Watch this!"

Flugg's Law

When you need to knock on wood is when you realize that the world is composed of vinyl, naugahyde and aluminum.

Slick's Three Laws of the Universe

• Nothing in the known universe travels faster than a bad check.
• A quarter-ounce of chocolate = four pounds of fat.
• There are two types of dirt: the dark kind, which is attracted to light objects, and the light kind, which is attracted to dark objects.

Mencken and Nathan's Second Law of The Average American

All the postmasters in small towns read all the postcards.

Wiker's Law

Government expands to absorb revenue and then some.

Mencken and Nathan's Ninth Law of The Average American

The quality of a champagne is judged by the amount of noise the cork makes when it is popped.

Mencken and Nathan's Fifteenth Law of The Average American

The worst actress in the company is always the manager's wife.

Mencken and Nathan's Sixteenth Law of The Average American

Milking a cow is an operation demanding a special talent that is possessed only by yokels, and no person born in a large city can ever hope to acquire it.

Sturgeon's Law

90% of everything is crud.

Preudhomme's Law of Window Cleaning

It's on the other side.

The Third Law of Photography

If you did manage to get any good shots, they will be ruined when someone inadvertently opens the darkroom door and all of the dark leaks out.

Van Roy's Law

An unbreakable toy is useful for breaking other toys.

Atwoods corollary

No books are lost by lending except the ones you particularly wanted to keep.

Johnson's third law

If you miss one issue of a magazine, it will be the one that contains the article or story you were most anxious to read.

Corollary to Johnson's third law

All of your friends either missed it, lost it or threw it away.

Harper's magazine law

You never find the article until you replace it.

Zymurgy's first law of evolving system dynamics

Once you open a can of worms, the only way to recan them is to use a larger can (older worms never die, they just worm their way into larger cans).