In the 19th century, many scientists subscribed to the belief that the human population can be divided into races. The term "racism" is a noun describing the state of being racist, i.e., subscribing to the belief that the human population can or should be classified into races with differential abilities and dispositions, which in turn may motivate a political ideology in which rights and privileges are differentially distributed based on racial categories. The term "racist" may be an adjective or a noun, the latter describing a person who holds those beliefs. The origin of the root word "race" is not clear. Linguists generally agree that it came to the English language from Middle French, but there is no such agreement on how it generally came into Latin-based languages. A recent proposal is that it derives from the Arabic "ra's", which means "head, beginning, origin" or the Hebrew "rosh", which has a similar meaning. Early race theorists generally held the view that some races were inferior to others and they consequently believed that the differential treatment of races was fully justified. These early theories guided pseudo-scientific research assumptions; the collective endeavors to adequately define and form hypotheses about racial differences are generally termed scientific racism, though this term is a misnomer, due to the lack of any actual science backing the claims.