In his submission, titled "Onderzoek naar het nut der zendelingen en zendelings-genootschappen" (English: Examination of the usefulness of missionaries and missionary societies), Haafner condemned the behavior of missionaries in the colonies and argued for the complete withdrawal of all imperial powers, citing Voltaire, Rousseau, Bartolomé de las Casas, Bartholomäus Ziegenbalg, Pierre François Xavier de Charlevoix, and Thomas Gage.