The term Eugenics was coined by Francis Galton in 1883, and since this moment, the exact definition has been a matter of debate. But the concept predates the term, as Plato already wrote about the application of selective breeding in human beings at 400 BCE, and this was already put in practice in Sparta, back in 650 BCE.
But it is generally conceived as the group of beliefs and practices aimed at the improvement of genetic quality in human populations. This could come through positive eugenics, which is the stimulation of reproduction in population with the desired characteristics. And through negatice eugenics, that are measures to make reproduction in the negative groups, or with the negative traits, harder. Such as the prohibition of marriages and birth control policies aimed at theses groups.
The controverse among this "science" grew harder after the World War II, and the Nuremberg trials, where Nazi officials stated that many of the Allied countris, such as the US and the UK, had Eugenics policies similar to some found in Nazi Germany.
After this major modern controverse, the agreement of the critics, and usual common sense, is that the parameters for positive or negative characteristics would always have a political aspect, corrupting the science. And scientifically speaking, that Eugenics results in losses in genetical diversity, that leads to inbreed depression.
However, nowadays, with the rise of genetic engineering, this belief is geeting new strenght and bringing new challenges to bioethicists and other specialists.
