13. A system comprising: one or more data remembrance components; one or more processors; a template stored in said one or more data remembrance components, said template specifying a first set of one or more assertions; one or more executable components that are stored in said one or more data remembrance components, and that execute on said one or more processors, and that retrieve or generate a first token that satisfies a first one of said first set of one or more assertions, and that create a first data structure that comprises one or more tokens that, together with an access request, allow a first principal to access a resource to be true under a policy, said one or more tokens comprising said first token; a guard that evaluates said first data structure and determines whether to allow said first principal access to said resource based on said access request and said one or more tokens; and an abduction component that abduces said first set of one or more assertions from information that comprises an access request for said first principal to access the resource, said abduction component not having in possession said first set of one or more assertions, said abduction component abducing said first said of one or more assertions by: receiving a first answer set and a second answer set, said first answer set comprising said first set of one or more assertions, said second answer set comprising a second set of one or more assertions, said first set of said one or more assertions and said second set of said one or more assertions each satisfying a condition that either said first set of one or more assertions or said second set of one or more assertions will, when presented to said guard, cause said guard to find that a query evaluates to true under a policy implemented by said guard; and determining that said first answer set is not subsumed by said second answer set.
14. The system of claim 13 , further comprising: a token store that stores a plurality of tokens, including said first token, wherein said one or more executable components comprise an assertion provider that makes a determination that said first token satisfies said first one of said first set of one or more assertions and retrieves said first token from said token store based on said determination.