The truth about the science of eugenics is that there is no science to eugenics. What passed for scientific method in the eugenics movement is almost laughable now; if it were not so disturbing. Eugenicists were trying to explain complex human behaviors based on second hand accounts and in some cases heresy.
Researchers were often unable to interview more than one or two generations of a family, due to mortality. This meant that information about previous generations had to come from the accounts of children, grandchildren and friends. (Dolan) In some cases accounts were taken from neighbors and ...