His principal philosophical works are De immortalitate animi (1518 and 1524); De intellectu et daemonibus; De infinitate primi motoris quaestio and Opuscula moralia et politica.
Accordingly, when the work was published at Paris in August 1641, under the title of Meditationes de prima philosophia ubi de Dei existentia et animae immortalitate (though it was in fact not the immortality but the immateriality of the mind, or, as the second edition described it, animae humanae a corpore distinctio, which was maintained), the title went on to describe the larger part of the book as containing various objections of learned men, with the replies of the author.
In 1536 his didactic poem in Latin hexameters, De immortalitate animarum, was published at Lyons.
Palearii Verulani Opera), including four books of Epistolae and twelve Orationes besides the De immortalitate, was published at Lyons in 1552; this was followed by two others, at Basel, and several after his death, the fullest being that of Amsterdam, 1696.
His philosophic theory was identical with that of Pomponazzi, whose De immortalitate animi he defended and amplified in a treatise De mente humana.
About the same time Marsilio completed and published his treatise on the Platonic doctrine of immortality (Theologia Platonica de immortalitate animae), the work by which his claims to take rank as a philosopher must be estimated.
Theologici et historici (published by Mariana at Cologne, in 1609, containing in particular a tract, "De morte et immortalitate," and another, "De mutatione monetae") was put upon the index expurgatorius, and led to the confinement of its author by the Inquisition.