It is introduced by the world into human society. And the elimination of discrimination would constitute a grave error. The inequalities among humans and the ensuing conflicts are the fuel that feeds the engines of human development. Hopes, desires, aspirations and inspiration are all the derivatives of discrimination or of the wish to be favoured, or preferred over others. Disparities of money create markets, labour, property, planning, wealth and capital.
Mental inequalities lead to innovation and theory.
Knowledge differentials are at the heart of educational institutions, professionalism, government and so on. Osmotic and diffusive forces in human society are all the results of incongruences, disparities, differences, inequalities and the negative and positive emotions attached to them. The passengers of the first class were preferred because they paid more for their tickets. There is nothing morally wrong with this. There is no practical or philosophical difference between an expensive liver transplant and a place in a life boat.