(1) Parkinson’s: work expands to fill the time available for its completion
(2) Hofstadter’s: it always takes longer than you expect, even when you take into account Hofstadter’s Law
(3) Gates’s: most people overestimate what they can do in one year and underestimate what they can do in ten years
(4) Goodhart’s: when a measure becomes a target, it ceases to be a good measure
(5) Hanlon’s: never attribute to malice that which is adequately explained by stupidity (or, don’t invoke conspiracy when ignorance and incompetence suffice, as conspiracy implies intelligence)
(6) Acton’s: power tends to corrupt, and absolute power corrupts absolutely
(7) Amara’s: we tend to overestimate the effect of a technology in the short run and underestimate the effect in the long run
(8) Benford’s: in a diverse collection of unrelated statistics, a given statistic has roughly a 30% chance of starting with the digit 1
(9) Betteridge’s: any headline which ends in a question mark can be answered with the word ‘no’
(10) Brooks’s: adding manpower to a late software project makes it later
(11) Chesterson’s: reforms should not be made until the reasoning behind the existing state of affairs is understood
(12) Claasen’s: usefulness = log(technology)
(13) Clarke’s: when a distinguished elderly scientist states that something is possible, they are almost certainly right, but when they state something is impossible, they are probably wrong
(14) Cromwell’s: nothing but logical impossibilities have a prior probability of 0 or 1
(15) Cunningham’s: the best way to get the right answer on the Internet is not to ask a question; it’s to post the wrong answer
(16) Doctorow’s: when someone puts a lock on a thing you own, against your wishes, and doesn’t give you the key, they’re not doing it for your benefit
(17) Moore’s: computation per dollar grows exponentially (or: number of transistors per circuit doubles roughly every 24 months)
(18) Eroom’s: drug discovery is becoming slower and more expensive over time, despite improvements in technology
(19) Gell-Mann’s: you’ll believe articles outside your area of expertise, even after acknowledging that neighboring articles in your area of expertise are completely wrong
(20) Gibson’s: for each PhD (to use as an expert witness for one side), there exists an equal and opposite PhD
(21) Godwin’s: as an online discussion grows longer, the probability of a comparison involving Nazis or Hitler approaches one
(22) Miller’s: to understand what another person is saying, you must assume that it is true and try to imagine what it could be true of
(23) Greenspun’s: any sufficiently complicated C program contains an ad hoc, informally specified, bug-ridden, slow implementation of half of Common Lisp
(24) Hebb’s: neurons that fire together wire together
(25) Hubble’s: galaxies recede from an observer at a rate proportional to their distance to that observer
(26) Hume’s: normative statements (about what’s moral/immoral) cannot be deduced exclusively from descriptive statements
(27) Humphrey’s: conscious attention to a task normally performed automatically can impair its performance
(28) Kranzberg’s: technology is neither good nor bad; nor is it neutral
(29) Lamarck’s: use it or lose it (evolutionarily speaking, but also in the brain)
(30) Lewis’s: the comments you’ll inevitably find on any article about feminism justify feminism
(31) Littlewood’s: individuals can expect miracles to happen to them, at the rate of about one per month
(32) Maes–Garreau’s: favorable predictions about future technology will fall at the latest possible date they can come true and still remain in the lifetime of the predictor
(33) Metcalfe’s: the value of a networked system grows as approximately the square of the number of users of the system
(34) Morley-Souter’s: there is porn of it (no exceptions)
(35) Dunbar’s: most people can’t maintain stable social relationships with more than 150 people
(36) Murphy’s: anything that can go wrong will go wrong
(37) Alder’s: what cannot be settled by experiment (at least in principle) is not worth debating
(38) O’Sullivan’s: all organizations that are not explicitly right-wing will over time become left-wing
(39) Pareto’s: for many phenomena, 80% of consequences stem from 20% of the causes (or: most of the effects are produced by just a few of the causes)
(40) Peter’s: in a hierarchy, every employee tends to be promoted to his level of incompetence
(41) Pourenelle’s: in bureaucracy, those devoted to the bureaucracy tend to gain and keep control, while those devoted to the goals they are supposed to be achieving tend to lose influence
(42) Poisson’s: for independent random variables with a common distribution, the average of these tends to the true mean as sample size increases
(43) Putt’s: technology is dominated by two types of people; those who understand what they do not manage and those who manage what they do not understand
(44) Rosenthal’s: high expectations lead to an increase in performance; low expectations lead to a decrease in performance
(45) Schneier’s: any person can invent a security system so clever that she or he can’t think of how to break it
(46) Shermer’s: any sufficiently advanced extraterrestrial intelligence is indistinguishable from God
(47) Zipf’s: the frequency of use of the nth-most-frequently-used word in any natural language is approximately inversely proportional to n (few words are used often; most are used rarely)
(48) Wirth’s: software gets slower more quickly than hardware gets faster
(49) Sturgeon’s: ninety percent of everything is crud
(50) Stigler’s: no discovery is named after its original discoverer, including this one

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