He worked in the East Indies until 1848, when he received an official reprimand from the Dutch government for publicizing his views critical of colonialism; consequently he was forced to resign.
Ia bekerja di Hindia Belanda sampai tahun 1848, ketika dia mendapat teguran resmi dari pemerintah Belanda karena mempublikasikan pandangannya yang kritis terhadap kolonialisme; akibatnya ia terpaksa mengundurkan diri.