Philosopher and founding member of the Sociedade Positivista do Rio de Janeiro, Miguel Lemos was born in Niterói, in the state of Rio de Janeiro, on November 25, 1854. He studied engineering at the Escola Central do Rio de Janeiro, but interrupted his studies in 1877 to travel to Paris, where he remained until 1881 and met Pierre Laffitte, Émile Littré, and other Positivists. Back in Brazil, Lemos helped found the Igreja Positivista do Brasil (Positivist Church of Brazil) in Rio de Janeiro. From that point on, he dedicated himself almost exclusively to the work of the Apostolado Positivista (Positivist Apostolate), editing the Circulares Anuais (annual newsletters) and publishing pamphlets on Positivism for the Igreja. His writings reflected the opinion of the Apostolado on issues such as the abolition of slavery, republican ideals, orthography, and diplomacy. Miguel Lemos cultivated an orthodox form of Positivism that later led to disagreements with other positivists, such as Laffitte and Littré. He emphasized that faith should be demonstrable and be founded on seven principles”: it must be real, useful, right, precise, organic, relative, and pleasing. These were the guiding tenets of the Positivist Church of Brazil. Lemos died in 1917 in Petrópolis, in the state of Rio de Janeiro.