The monogenists have at first made great efforts to furnish such a demonstration, but without success.
The monogenists are thus deprived of their principal basis and their sole scientific argument.
The monogenists then resorted to an argumentation still more indirect.
monogenism mo·nog·e·nism (mə-nŏj'ə-nĭz'əm)
The theory that all human beings are descended from a single pair of ancestors.