Giovanni Maria Tolosani

Giovanni Maria Tolosani (c.1471 – 22 January 1549), also known by the pseudonym Joannes Lucidus Samotheus, was an Italian theologian, writer, mathematician, and astronomer. Born in Colle di Val d'Elsa to a jurist father, Leonardo, he joined the Dominican order in 1487 and remained associated with it until his death. He held positions as vice-prior at San Marco and contributed to the chronicle of San Marco and San Maria del Sasso. Tolosani was involved in efforts to reform the Roman calendar during the Fifth Council of the Lateran, authoring works such as *De computatione annorum Domini* and *Apusculum de correctione calendarii*. He also published under a pseudonym on topics including the alignment of the calendar with seasonal changes. Known for his critique of Copernican heliocentric theory, Tolosani described Copernicus in 1546 as deficient in physics, dialectics, and Holy Scripture, while praising his mathematical expertise. His writings were highly regarded by his friend Bartolommeo Spina, a philosopher and Master of the Sacred Palace. Tolosani’s works include *Compendio di sphera et machina del mondo* (1514) and *De emendationibus temporum* (1537). He died in Siena on 22 January 1549.