According to Condorcet (1743–1794), the true philosopher has one essential aim: to improve the fate of all mankind, without distinction of nationality, religion or race. Anti-slavery movements are an example of what one should promote.
The philosophers of different nations embracing, in their meditations, the entire interests of man, without distinction of country, of colour, or of sect, formed, notwithstanding the difference of their speculative opinion, a firm and united phalanx against every description of error, every species of tyranny. Animated by the sentiment of universal philanthropy, they declaimed equally against injustice, whether existing in a foreign country, or exercised by their own country against a foreign nation. They impeached in Europe the avidity which stained the shores of America, Africa, and Asia with cruelty and crimes. The philosophers of France and England gloried in assuming the appellation, and fulfilling the duties, of friends to those very Negroes whom their ignorant oppressors disdained to rank in the class of men. The French writers bestowed the tribute of their praise on the toleration granted in Russia and Sweden, while Beccaria refuted in Italy the barbarous maxims of Gallic jurisprudence.
Marie-Jean-Antoine-Nicolas de Caritat, Marquis de Condorcet, Outlines of an Historical View of the Progress of the Human Mind (1794).
Read the free English text online (1795 edition): https://books.google.co.uk/books?id=SLs8AAAAYAAJ &dq=condorcet america africa asia&pg=PA256
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