Kazimierz Łyszczyński

Kazimierz Łyszczyński, known in English as Casimir Liszinski, was a Polish nobleman, philosopher and soldier in the service of the Sapieha family, born on 4 March 1634 at Łyszczyce in what is now the Brest Region of Belarus. He studied philosophy for eight years as a Jesuit, left the order, and served as a supply judge in legal cases against the Jesuits over estates, and he also sat in the Sejm of the Polish-Lithuanian Commonwealth. He wrote the treatise De non-existentia Dei, On the Non-Existence of God, which argued that God is a concept made by human beings and that religions are human inventions, and which is regarded as the first Polish philosophical treatise to present reality from an atheistic standpoint. A debtor denounced him and handed a copy of the manuscript to the bishop of Poznan, and in 1689 the Sejm condemned him for atheism. He was executed in Warsaw on 30 March 1689, and his trial has been criticised as a case of legalised religious murder.