Quotation by Hannah Arendt

Forced labor as a punishment is limited as to time and intensity. The convict retains his rights over his body; he is not absolutely tortured and he is not absolutely dominated. Banishment banishes only from one part of the world to another part of the world, also inhabited by human beings; it does not exclude from the human world altogether. Throughout history slavery has been an institution within a social order; slaves were not, like concentration-camp inmates, withdrawn from the sight and hence the protection of their fellow-men; as instruments of labor they had a definite price and as property a definite value. The concentration-camp inmate has no price, because he can always be replaced; nobody knows to whom he belongs, because he is never seen. From the point of view of normal society he is absolutely superfluous.