Definitionv1
Half-life of information: the time period required for half
Half-life of information: the time period required for half of a body of knowledge in a field to be superseded or proven wrong
Why This Is a Definition
This definition clearly names the term 'half-life of information', identifies its genus (time period for knowledge decay), and states its differentia (for half of knowledge in a field to be superseded or proven wrong). It distinguishes this from mere knowledge obsolescence by specifying the precise statistical measure of decay.
Source Lessons
L-0134
The half-life of information
Different types of information decay at different rates. Some knowledge stays relevant for centuries. Some is obsolete by lunch. Knowing which is which changes what you pay attention to.
L-0166
Temporal context shifts meaning
What was true in one time period may not be true in another — always note the when.