Castor et Pollux (Castor and Pollux) is an opera by Jean-Philippe Rameau, first performed on 24 October 1737 by the Académie royale de musique at its theatre in the Palais-Royal in Paris. The librettist was Pierre-Joseph-Justin Bernard, whose reputation as a salon poet it made. This was the third opera by Rameau and his second in the form of the tragédie en musique (if the lost Samson is discounted). Rameau made substantial cuts, alterations and added new material to the opera for its revival in 1754. Experts still dispute which of the two versions is superior. Whatever the case, Castor et Pollux has always been regarded as one of Rameau's finest works. Composition history Charles Dill proposes that Rameau had composed the 1737 opera just after working with Voltaire on the opera "Samson" that was never completed, after which he composed "Castor et Pollux" implementing Voltaire's aesthetics. For example, Voltaire sought the presentation of static tableaus that expressed emotion, as in the first act of the 1737 version which begins at the scene of Castor's tomb with a Chorus of Spartans singing "Que tout gemisse", followed by a recitative between Telaire and Phoebe in which the former is grieving the loss of her lover Castor, and culminating in Telaire's lament aria "Tristes apprets". Dill notes that in contrast, the 1754 version begins with much more background behind the story of Telaire's love for Castor and depicts his death at the end. The events in Act I of the 1737 version appear in Act II of the 1754 version. Dill claims that Voltaire was more interested in music than action in opera. Moreover, Dill notes a difference in the plots between in the two versions. In the 1737 version, the main concern is for the moral dilemma between love and duty that Pollux faces: should he pursue his love of Telaira or rescue his brother? Of course, he chooses the latter. In the 1754 version, Dill remarks that that plot is more concerned with the tests that Pollux must face: he must kill Lynceus, persuade Jupiter not to oppose his journey into the Underworld, and persuade Castor not to accept the gift of immortality. While some scholars (such as Cuthbert Girdlestone, Paul-Marie Masson, and Graham Sadler) have assumed that the 1754 version was superior, Dill argues that Rameau made the changes of 1754 at a different point in his career. In