Brandt's medical ethics, particularly regarding euthanasia, were influenced by Alfred Hoche, whose courses he attended. Like many other German doctors of the period, Brandt came to believe that the health of society as a whole should take precedence over that of its individual members. Because society was viewed as an organism that had to be cured, its weakest, most invalid and incurable members were only parts that should be removed. Such hapless creatures should therefore be granted a "merciful death" (Gnadentod). In addition to these considerations, Brandt's explanation at his trial for his Criminal actions – particularly ordering experimentation on human beings – was that "... Any personal code of ethics must give way to the total character of the war". Historian Horst Freyhofer asserts that, in the absence of at least Brandt's "tacit" approval, it is highly unlikely that the grotesque and cruel medical experiments for which the Nazi doctors are infamous, could have been performed. Brandt and Hitler discussed multiple killing techniques during the initial planning of the euthanasia program, during which Hitler asked Brandt, “which is the most humane way;” Brandt suggested the use of carbon monoxide gas, whereupon Hitler gave his approval and instructed Brandt to reach out to other Physicians and begin to coordinate the mass killings.