5 ▁Hart sh or ne ▁purs ued ▁further ▁studies ▁in ▁Europe . ▁He ▁attended ▁the ▁University ▁of ▁Fre ib urg , ▁where ▁he ▁studied ▁under ▁the ▁phenomen ologist ▁Edmund ▁Hus ser l , ▁and ▁also ▁the ▁University ▁of ▁Mar burg , ▁where ▁he ▁studied ▁under ▁Martin ▁He ide g ger . ▁He ▁then ▁returned ▁to ▁Harvard ▁University ▁as ▁a ▁research ▁fellow ▁from ▁ 1 9 2 5 – 2 8 , ▁where ▁he ▁and ▁Paul ▁We iss ▁edited ▁the ▁Collect ed ▁Pap ers ▁of ▁Charles ▁Sand ers ▁Pe ir ce ▁v . ▁ 1 – 6 ▁and ▁spent ▁a ▁sem ester ▁assist ing ▁Alfred ▁North ▁White head . ▁ ▁Career ▁ ▁After ▁Hart sh or ne ▁worked ▁at ▁Harvard ▁University , ▁he ▁became ▁a ▁professor ▁of ▁philosophy ▁at ▁the ▁University ▁of ▁Chicago ▁( 1 9 2 8 – 1 9 5 5 ), ▁and ▁was ▁also ▁a ▁member ▁of ▁the ▁University ' s ▁Feder ated ▁The ological ▁Fac ulty ▁( 1 9 4 3 – 1 9 5 5 ). ▁He ▁then ▁taught ▁at ▁Em ory ▁University ▁( 1 9 5 5 – 6 2 ), ▁followed ▁by ▁the ▁University ▁of ▁Texas ▁( 1 9 6 2 – ret irement ). ▁He ▁published ▁his ▁last ▁article ▁at ▁age ▁ 9 6 ▁and ▁delivered ▁his ▁last ▁lecture ▁at ▁ 9 8 . ▁ ▁In ▁addition ▁to ▁his ▁long ▁teaching ▁career ▁at ▁the ▁previous ▁three ▁univers ities , ▁Hart sh or ne ▁was ▁also ▁appointed ▁as ▁a ▁special ▁lect urer ▁or ▁visit ing ▁professor ▁at