Superstition is to religion what astrology is to astronomy the mad daughter of a wise mother. These daughters have too long dominated the earth.

In this quote, Voltaire draws a sharp comparison between superstition and religion, and between astrology and astronomy, suggesting that both superstition and astrology are misguided or distorted versions of something initially wise and grounded. He argues that superstition, like astrology, arises from human curiosity but lacks the reason, logic, and scientific grounding of their parent forms, religion and astronomy. Voltaire describes superstition and astrology as the "mad daughter of a wise mother," implying that they are irrational and illogical offshoots of more structured, thoughtful traditions. The quote suggests that these distortions have had too much influence on society, dominating human thinking and behavior for far too long.

Voltaire, a leading figure of the Enlightenment and a fierce critic of religious dogma, was deeply concerned with the influence of irrational beliefs on society. His works, such as Candide and Letters on England, critique the role of organized religion and superstitions in limiting reason and freedom. The quote reflects his belief in the importance of rational thought, empirical evidence, and science in understanding the world, and his skepticism towards beliefs that cannot be logically or scientifically justified. By likening superstition to astrology, Voltaire highlights how both are seen as pseudosciences that are often accepted without critical examination.

The origin of this quote lies within Voltaire’s broader critique of religion and irrational beliefs in the 18th century. The Enlightenment was an era that celebrated reason, science, and humanism, challenging the authority of religious institutions and traditional beliefs that had long dominated European society. Voltaire, as one of the prominent philosophes of the movement, used his wit and sharp critiques to advocate for a society that valued intellectual freedom and enlightened thought. This quote reflects his frustration with the persistence of superstition and the ways it undermines the progress of human understanding.

Ultimately, Voltaire's quote is a call to reject the dominance of irrational and superstitious thinking in favor of rationality, science, and critical inquiry. By framing superstition and astrology as the “daughters” of religion and astronomy, he urges society to free itself from the constraints of unfounded beliefs and embrace more enlightened, logical ways of understanding the world. In doing so, Voltaire reinforces the values of the Enlightenment and the need to move beyond outdated, dogmatic systems that hinder human progress.