Isaac Orobio de Castro

Balthazar (Isaac) Orobio de Castro (c.1617 in Bragança, Portugal – November 7, 1687 in Amsterdam), was a Portuguese Jewish philosopher, physician and religious apologist.

When married and father of a family, De Castro was, at the instigation of a servant whom he had punished for theft, denounced to the Inquisition as an adherent of Judaism, and thrown into a dark and narrow dungeon, where he remained for three years, subjected to the most frightful tortures.

He thereupon went to Toulouse, where he became professor of medicine at the university, at the same time receiving from Louis XIV the title of councilor; but, weary at last of hypocrisy and dissimulation, he went to Amsterdam about 1666, and there made a public confession of Judaism, adopting the name "Isaac."

His work entitled Certamen Philosophicum Propugnatæ Veritatis Divinæ ac Naturalis Adversus J. Bredenburgi Principia was published at Amsterdam, 1684 (reprinted 1703 and 1731).

They are: Long after De Castro's death a Jew by the name of Henriquez published an alleged work of his in French under the title Israel Vengé, claiming it to have been originally written in Spanish (London, 1770).