11. A system for storing and using a set of observations of real-world events and actions, the system comprising: a cluster generator for generating clusters based on the set of observations, each cluster representing correlations between events and actions in a subset of observations in the set of observations; and a graph processor coupled to the cluster generator for processing the clusters into a first linked graph based on a set of rules to identify correlations between the events and actions, the first linked graph tagged to indicate the correlations between the events and the actions; wherein the cluster generator presupposes an event as reversible unless an observation contradicting reversibility of the event is obtained, and wherein the graph processor tags an edge associated with the irreversible event as having uncertain correlations with actions that are irreversible.
11. A system for storing and using a set of observations of real-world events and actions, the system comprising: a cluster generator for generating clusters based on the set of observations, each cluster representing correlations between events and actions in a subset of observations in the set of observations; and a graph processor coupled to the cluster generator for processing the clusters into a first linked graph based on a set of rules to identify correlations between the events and actions, the first linked graph tagged to indicate the correlations between the events and the actions; wherein the cluster generator presupposes an event as reversible unless an observation contradicting reversibility of the event is obtained, and wherein the graph processor tags an edge associated with the irreversible event as having uncertain correlations with actions that are irreversible. 19. The system of claim 11 , wherein the graph processor generates a second linked graph for another set of observations by modifying or expanding the first linked graph.