(Lat., what is given) A piece of evidence considered as fixed for the purpose in hand. What is taken as a datum may change as changes of theory and evidence arise. Something would be absolutely a datum if it were incorrigible, but many theorists of knowledge tend to be nervous about regarding anything as absolutely given, for although some things may serve as a basis for particular enquiries, this does not protect them from eventual challenge. See epistemology, protocol statements, verification ; see also sense datum.
Philosophy dictionary. Academic. 2011.