Cabals will, from long practice, calcify so as to become extraordinarily traditional and conservative in their goals, as it is believed by the most powerful that any change threatens the established stability of the organization. Cabals will often believe they are performing acts that serve the public interest, the stability of the nation, the sanctity of the religion they support and so on - and that any act, no matter how vile, is acceptable so long as the ends are achieved.
MembershipWhile oligarchic in nature, membership in a cabal is very rarely considered a familial privilege. Such organizations usually insist that a pater or mater's descendents 'prove themselves' to the same degree as did the ancestor that proceeded them. Sometimes this is aided by the elder giving advice to the younger, to ensure a more likely approval ~ but this can also lead to parts of the organization that must be 'pruned' of certain families that have grown presumptuous or problematic. Execution of several dozen such family members and their closest companions is not unlikely.
Existing members are usually kept from the highest levels of knowledge by a series of 'circles,' where new candidates are kept on the outer edges, while those in the inner circle receive the greatest knowledge or privileges. Thus, those least likely to honor the cabal's principles also have the least amount of information to disseminate. Most everything that is known about cabals by the general public represents hearsay that has been started by those on the edge, who were never themselves in a position to know the full truth.