This is an updated version of an article published on 10 November 2009.
Rosenstock-Huessy's Law of Technology
All technology expands the space, contracts the time, and destroys the working group.
Sattingler's Principle
It works better if you plug it in. If it still doesn't work, switch it on.
Ninety-nine Rule of Project Schedules
The first ninety percent of the task takes ninety percent of the time, the last ten percent takes the other ninety percent.
Grosch's Law
Computing power increases as the square of the cost. If you want to do it twice as cheaply, you have to do it four times as fast.
Computer Rule
To err is human but to really foul things up requires a computer.
Lubarsky's Law of Cybernetic Entomology
There's always one more bug.
Gallois's Revelation
If you put tomfoolery into a computer, nothing comes out but tomfoolery. But this tomfoolery, having passed through a very expensive machine, is somehow ennobled, and no one dares to criticise it.
Westheimer's Rule
To estimate the time it takes to do a task: estimate the time you think it should take, multiply by two, and change the unit of measure to the next highest unit. Thus we allocate two days for a one-hour task.
Peers's Law
The solution to a problem changes the problem.
Gilb's 1st law of unreliability
Computers are unreliable, but humans are even more unreliable.
Gilb's 2nd Law of Unreliability
Any system which depends on human reliability is unreliable.
Gilb's 3rd Law of Unreliability
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.
These rules were coined by Thomas Gilb, a systems engineer.
Shipman's First Law
ICT capability is inversely related to seniority within an organisation.
Shipman's Second Law
The length of time required for a task is inversely related to its simplicity.
Freedman's Postulate
The reliability of computer systems is inversely related to the urgency of the task.
Allen's Axiom
When all else fails, read the instructions.
Gall's Second Principle of Systemantics
New systems generate new problems.
Coffee's observation
If you do not have anything to say, a word processor
will not say it ~ Peter Coffee
Peers's Law
The solution to a problem changes the problem.
Richards' First Law of Data Security
Don't buy a computer.
Richards' Second Law of Data Security
If you do buy a computer, don't turn it on.
Thanks to David Harley for providing me with these last two rules.
First published in InTegrate, March 1995.
You may also find 7 rules for ICT teachers, co-ordinators and leaders interesting.
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