Emmanuel Joseph Sieyès (ĕmänüĕl´ zhôzĕf´ syāĕs´), 1748–1836, French revolutionary and statesman. He was a clergyman before the Revolution and was known as Abbé Sieyès. His pamphlet Qu'est-ce que le tiers état? [What is the third estate?] (1789), attacking noble and clerical privileges, was popular throughout France, and he was elected deputy from the third estate to the States-General of 1789. He advocated the formation of the national assembly, and participated in the writing of the Declaration of the Rights of Man and Citizen and the constitution of 1791 (see French Revolution). He made his chief contributions in 1789–91 with the theory of national sovereignty and representation, and the distinction between active and passive citizens, which restricted the vote to men of property. As a member of the Convention he voted for the execution of King Louis XVI. His prudent silence enabled him to live through the Reign of Terror, and after the overthrow of Maximilien Robespierre on 9 Thermidor (1794), Sieyès again became active in the government. In 1799 he entered the Directory. Later that year he conspired with Napoleon Bonaparte (see Napoleon I) in the overthrow of the Directory by the coup of 18 Brumaire. Sieyès became, with Bonaparte and Roger Ducos, one of the three provisional consuls. His sketch for the constitution of the year VIII was, however, changed in decisive points by Bonaparte, and Sieyès and Ducos were replaced (Dec., 1799) as consuls. He became senator and senator of the empire and, after the Bourbon restoration, lived in exile (1816–30) in Brussels. The name also appears as Sieyes.