si ▁Wu ▁and ▁John ▁Rh odes , ▁both ▁of ▁the ▁University ▁of ▁California , ▁Ber keley . ▁In ▁the ▁ 1 9 6 0 s ▁Am bro se ▁was ▁a ▁visit ing ▁professor ▁at ▁the ▁University ▁of ▁Buenos ▁Aires , ▁Argentina . ▁He ▁is ▁noted ▁for ▁his ▁opposition ▁of ▁take over ▁of ▁South ▁American ▁countries ▁military ▁reg imes , ▁specifically ▁Argentina . ▁ ▁Political ▁activ ism ▁ ▁In ▁the ▁summer ▁of ▁ 1 9 6 6 , ▁while ▁a ▁visit ing ▁professor ▁at ▁the ▁University ▁of ▁Buenos ▁Aires ▁in ▁Argentina , ▁Am bro se ▁was ▁sever ely ▁be aten ▁along ▁with ▁Argent in ian ▁fac ulty ▁members ▁and ▁students ▁by ▁Argent in ian ▁military ▁police . ▁This ▁occurred ▁shortly ▁after ▁a ▁military ▁regime ▁took ▁over ▁public ▁univers ities ▁in ▁Argentina . ▁Am bro se ▁respond ed ▁by ▁bringing ▁several ▁of ▁the ▁best ▁and ▁bright est ▁students ▁from ▁the ▁University ▁of ▁Buenos ▁Aires ▁back ▁to ▁M IT ▁with ▁him . ▁Am bro se ▁is ▁often ▁ren owned ▁amongst ▁Latin ▁American ▁intellect uals ▁for ▁bringing ▁attention ▁to ▁right - wing ▁dict ator ships ▁in ▁South ▁America . ▁ ▁In ▁ 1 9 6 7 , ▁Am bro se ▁signed ▁a ▁letter ▁declaring ▁his ▁intention ▁to ▁refuse ▁to ▁pay ▁tax es ▁in ▁protest ▁against ▁the ▁U . S . ▁war ▁against ▁Vietnam , ▁and ▁ur ging ▁other ▁people ▁to ▁also ▁take ▁this ▁stand . ▁ ▁References ▁ ▁External ▁links ▁ ▁Category : 2 0 th - century ▁American ▁mathemat icians ▁Category : American ▁tax ▁res ister