Sui generis
In sociology, the "sui generis" is what has been externalized, then internalized in the overall public and becomes a part of society that simply exists in its construct. It is not something that is not thought to have been created, because it is imbedded in everyone's way of thinking and being. Instances include the idea of love, or going to school, or clothing belonging to a specific gender. These examples are "sui generis" for they simply exist in society and are widely accepted without thoughts of where they come from or how they were created.
Social teachings of Pope Pius XII
In 1950, Pius XII promulgated "Humani generis" which acknowledged that evolution might accurately describe the biological origins of human life, but at the same time criticized those who use it as a religion, who "imprudently and indiscreetly hold that evolution... explains the origin of all things". While "Humani generis" was significant as the first occasion on which a pope explicitly addressed the topic of evolution at length, it did not represent a change in doctrine for the Roman Catholic Church. As early as 1868, Cardinal John Henry Newman wrote, "the theory of Darwin, true or not, is not necessarily atheistic; on the contrary, it may simply be suggesting a larger idea of divine providence and skill." The encyclical issues a clear no to another scientific opinion popular at the time, polygenism, "the scientific hypothesis that mankind descended from a group of original humans."