▁it ▁in ▁a ▁certain ▁light ; ▁mask ing ▁through ▁the ▁(" meta - the oret ical ") ▁interpretation ▁of ▁the ▁overall ▁significance ▁of ▁a ▁quant itative ▁result . ▁ ▁Data ▁may ▁be ▁accepted ▁as ▁a ▁valid ▁result , ▁but ▁dismiss ed ▁as ▁irrelevant ▁or ▁un important ▁in ▁a ▁given ▁context , ▁and ▁therefore ▁not ▁worth ▁pay ing ▁attention ▁to ; ▁or ▁convers ely , ▁the ▁importance ▁of ▁specific ▁data ▁may ▁be ▁highlight ed ▁as ▁being ▁more ▁important ▁than ▁other ▁related ▁facts . ▁ ▁S ources ▁of ▁the ▁concept ▁ ▁Marx ' s ▁studies ▁of ▁Greek ▁philosophy ▁The ▁the atr ical ▁mask , ▁express ing ▁an ▁acting ▁role , ▁was ▁supposed ly ▁first ▁invent ed ▁in ▁the ▁West ▁by ▁the ▁Greek ▁actor ▁Th es pis ▁of ▁Att ica ▁( 6 th ▁century ▁BC ) ▁and ▁the ▁Greek ▁Arist ot elian ▁phil os opher ▁The op hr ast us ▁( cir ca ▁ 3 7 1 – 2 8 7 ▁BC ) ▁is ▁cred ited ▁with ▁being ▁the ▁first ▁in ▁the ▁West ▁to ▁define ▁human ▁character ▁in ▁terms ▁of ▁a ▁typ ology ▁of ▁personal ▁strength s ▁and ▁weak ness es . ▁Indeed , ▁Marx ' s ▁idea ▁of ▁character ▁mask s ▁appears ▁to ▁have ▁origin ated ▁in ▁his ▁doctor al ▁studies ▁of ▁Greek ▁philosophy ▁in ▁ 1 8 3 7 – 3 9 . ▁At ▁that ▁time , ▁the ▁theatre ▁was ▁one ▁of ▁the ▁few ▁places ▁in ▁Germany ▁where ▁opinions ▁about ▁public ▁affairs ▁could ▁be ▁fairly ▁freely ▁a ired , ▁if ▁only ▁in ▁fict ional