Even the Order Issued to the Directors of Hospitals, Outpatients' Clinics and Other Infirmaries by the Minister for Spiritual, Educational and Medical Affairs in 1900 contained the stipulation that medical experiments on human beings were only permissible if the persons in question had given their assent to participation and this declaration had been preceded by appropriate guidance as to the adverse consequences that could potentially result from the intervention. Informed consent has since constituted a fundamental principle underlying the ethics of research. Certain aspects of this fundamental principle continue to be discussed, however, including for example the question of which conditions a person must satisfy in order to be able to give informed consent and the type of acts to which a person may or may not consent.