ACONCIO (ACONCIO, CONCIO), GIACOMO. — Born at Ossana in Trentino at the beginning of the sixteenth century, he died in England; according to Cheynel, he was still alive in 1613. Because of his antitrinitarian doctrines, he had to leave Italy in 1557, and joined other Italian refugees in Switzerland, about whom Comander wrote: “they are quarrelsome and restless, argue over every trifle, do not wish to be instructed, and cannot be moved from their stubbornness.” From Switzerland he went to England around 1560 and dedicated his famous book Stratagemata Satanae to Queen Elizabeth.
It seems that in this book A. was the precursor of certain modern Protestants, since he writes that it is sufficient to know and profess a few articles of faith, derived directly from Scripture, while considering all the others indifferent. His purpose, in reducing the dogmas of faith to very few, was to induce the sects to tolerate one another, a tolerance from which he did not exclude Catholicism. Among the indifferent dogmas he also included the Incarnation; indeed, in his letter to the archbishop of Canterbury, Grindal (1575–83), he clearly denied the divinity of Jesus Christ. He also wrote De Methodo sive recta investigandarum tradendarumque scientiarum ratione, in which he rejected ordinary dialectic and proposed reaching the truth by repeatedly breaking down and recomposing a subject and examining it from different points of view.