Fluents and Actions
In the event calculus, fluents are reified. This means that statements are not formalized as predicates but as functions. A separate predicate is used to tell which fluents hold at a given time point. For example, means that the box is on the table at time ; in this formula, is a predicate while is a function.
Actions are also represented as terms. The effects of actions are given using the predicates and . In particular, means that, if the action represented by the term is executed at time, then the fluent will be true after . The predicate has a similar meaning, with the only difference being that will be false and not true after .
Read more about this topic: Event Calculus
Famous quotes containing the word actions:
“The mob is man voluntarily descending to the nature of the beast. Its fit hour of activity is night. Its actions are insane like its whole constitution. It persecutes a principle; it would whip a right; it would tar and feather justice, by inflicting fire and outrage upon the houses and persons of those who have these. It resembles the prank of boys, who run with fire-engines to put out the ruddy aurora streaming to the stars.”
—Ralph Waldo Emerson (1803–1882)