Kammala wannan jumla: Matthiessen yana daya daga cikin maza da mata masu ilimi da yawa a fadin wadanda suka amsa da himma ga fashewar juyin juya hali a Paris a 1789. A watan Yulin 1790, ya kasance daya daga cikin manyan masana ilimi na Hamburg kimanin tamanin da suka halarci "Bikin Juyin Juya Hali" wanda Sieveking ya shirya kuma aka gudanar a wani lambun mashaya a Harvestehude don bikin cika shekaru ɗaya na juyin juya hali na Hamburg.
Fuskantar Bastille. A lokacin hunturu na 1790/91 ya zauna a Paris, ya zama memba na "Club 87" kuma ya kulla dangantaka da de La Rochefoucauld. A watan Yulin 1791 ya dawo Hamburg inda aka zabe shi a matsayin memba na "Kollegium der Armenanstalt", wanda ke kula da Caspar Voght. Daga baya tafiye-tafiyensa zuwa Paris ya zama na yau da kullun, kuma ya mai da shi fifikon kansa don ba da tallafi ga mutanen Paris da ke cikin bukata. A lokacin shekarunsa na ƙarshe yana ba da tallafi ga iyalai tamanin, yana ziyartar su duka muddin ƙarfinsa ya ba da izini.