Silbiger identifies two more cultural dynamics that he argues contribute to disproportionate achievement. The first is a strong emphasis on individual intellectual distinctiveness: the cultural expectation not just of competence but of original thinking, personal interpretation, and the development of a distinctive voice and perspective. This manifests in the debate culture he described earlier, but it goes further: the expectation that each generation will not simply repeat what was transmitted but will interpret, challenge, and extend it. This produces individuals who are uncomfortable with being merely adequate or merely typical. The cultural norm is toward originality and excellence, not conformity. The second dynamic Silbiger discusses is what he carefully and thoughtfully describes as a drive to prove oneself: a persistent motivation to demonstrate capability and worth that he traces partly to historical exclusion. Communities that were denied access to certain professions, universities, and social positions and were then given access developed, in some members, an extraordinary drive to demonstrate that the exclusion had been unjust. Silbiger is careful to distinguish this from a simple account of adversity producing motivation. Not all adversity produces this effect. What produces it, he argues, is a specific combination: a community that transmitted the belief that the individuals within it had something valuable to contribute, combined with an external denial of the opportunity to prove it. When the denial was finally lifted, the combination of internal conviction and long-frustrated ambition produced extraordinary effort.