1. A method of managing information comprising: providing a plurality of rules and a plurality of abstractions, wherein each of the plurality of abstractions represents at least one of a class of entities or a class of actions having a role in managing of the information and each of the plurality of rules comprises an expression having a variable, and the variable is defined in a first abstraction; determining a subset of the plurality of rules and abstractions relevant to a target; modifying the subset of rules and abstractions, wherein the modified subset of rules and abstractions is logically equivalent to the subset of rules and abstractions; associating the modified subset of rules and abstractions to the target; for the target, controlling access to the information based on the modified subset of rules and abstractions; providing a rule having a first variable defined in the first abstraction of the subset of the plurality of rules and abstractions, wherein the first abstraction has a second variable defined in a second abstraction; and evaluating the second variable, wherein when the second variable evaluates to a constant, and the modifying the subset of rules and abstractions comprises removing the second variable from the first abstraction.
6. The method of claim 1 wherein the modifying the subset of rules and abstractions comprises replacing a constant subexpression in a rule with a constant, and an expression comprises at least one subexpression.