Lightning Talk: What do you mean by “is”?  - Duncan Jones

(1) ignition switch

variable

(2) car

(3) traffic

it depends

can only answer what the answer "was"

transactions: it's bad form to lock guests in their room

Example:

distance (influences time)

business rule containing "is"

do you mean

- quite recently

- a minute ago, 5 minutes ago

- defined location (priveleged observer)