▁ 1 9 6 5 , ▁and ▁her ▁M . A . ▁degree ▁from ▁Columbia ▁University ▁in ▁ 1 9 6 7 , ▁writing ▁her ▁th esis ▁on ▁De ▁element is : ▁Earth , ▁Water , ▁Air , ▁and ▁Fire ▁in ▁the ▁ 1 2 th ▁and ▁ 1 3 th ▁Cent uries . ▁She ▁completed ▁her ▁Ph . D . ▁in ▁history ▁and ▁philosophy ▁of ▁science ▁at ▁Indiana ▁University ▁in ▁ 1 9 7 1 . ▁Her ▁Ph . D . ▁th esis ▁was ▁The ▁Med ieval ▁Philosoph y ▁and ▁Bi ology ▁of ▁G row th : ▁Albert us ▁Magn us , ▁Thomas ▁Aqu inas , ▁ ▁Albert ▁of ▁Sax ony ▁and ▁Mars il ius ▁of ▁Ing hen ▁on ▁Book ▁I , ▁Chapter ▁V ▁of ▁Arist ot le ’ s ▁‘ De ▁ ▁generation e ▁et ▁cor ruption e ,’ ▁with ▁Trans l ated ▁Text s ▁of ▁Albert us ▁and ▁Thomas ▁Aqu inas . ▁ ▁Career ▁Cad den ▁taught ▁as ▁an ▁assistant ▁professor ▁in ▁the ▁Department ▁of ▁History ▁of ▁Science ▁at ▁Harvard ▁University ▁from ▁ 1 9 7 1 - 1 9 7 6 . ▁She ▁was ▁a ▁visit ing ▁lect urer ▁in ▁history ▁at ▁the ▁University ▁of ▁Colorado , ▁B ould er ▁in ▁ 1 9 7 7 - 1 9 7 8 . ▁She ▁taught ▁at ▁ ▁Ken y on ▁College ▁from ▁ 1 9 7 8 - 1 9 9 6 . ▁She ▁was ▁a ▁D ib ner ▁Vis iting ▁Histor ian ▁of ▁Science ▁at ▁Pur due ▁University ▁Cal