Introduction
Vygosky,Sovietpsychologistandfounderofthetheoryofculturalhistorydevelopment(1896～1934),wrotethebook"AdvancedMentalFunction"in1931andpublishedin1960.Thebookelaboratesontheauthor'sviewsonthesocialoriginandintermediarystructureofhumanadvancedmentalfunctions,aswellasthebasicprinciplesandapproachesforresearch.Hebelievesthatpeople'sadvancedpsychologicalfunctionsareproducedanddevelopedintheinteractionwithpeoplearoundthem,andarerestrictedbyhumancultureandhistory.Manusesmaterialtoolstoperformlaboroperations,whichseparateshimselffromtheanimalworld.Atthesametime,manusessymbols,words,languageandotherspiritualtoolsforspiritualproduction,sothathismentalfunctionundergoesaqualitativechangeandrisestoahigherstage.Theuseofmentaltoolsmakespeople'shigher-levelmentalfunctionshaveonemoreintermediarylinkthanthelower-levelmentalfunctionsinstructure,thusgivingthemanindirectnature.
Features
High-levelmentalfunctionshaveaseriesofcharacteristicsthataredifferentfromlow-levelmentalfunctions:theyarerandomandactive;theirlevelofreflectionischaracterizedbygeneralizationandabstraction;theyaresocialcultureTheproductofhistoricaldevelopment;ithasthecharacteristicsofindirectstructurewithsymbolsorwordsasthemedium.Fromtheperspectiveofindividualdevelopment,advancedmentalfunctionsareproducedanddevelopedinpeople'slaborpracticeandcommunication.Allhumanpsychologicalcharacteristicsaretheresultofthecontinuousinternalizationofexternalthings.
