A Philosopher Lecturing on the Orrery (sometimes called simply The Orrery) is a painting (oil on canvas, ca. 1766) by Joseph Wright of Derby depicting a public lecture about a model Solar System, with a lamp—in place of the Sun—illuminating the faces of the audience. Wright captures the spirit of the Enlightenment, with knowledge as a force of moral uplift for the audience of commoners under the tutelage of the natural philosopher. Consistent with the astronomical theme, the partially illuminated faces may represent the phases of the Moon, ranging from full (the children) to gibbous (the man standing on the left) to new (the figure seen from behind).