This little-known work by Jeremy Bentham, the great English philosopher and originator of utilitarianism, was considered so controversial when it was first published in 1822 that Bentham used the pseudonym of Philip Beauchamp. The focus of this critical treatise is natural religion, a school of thought that maintained one could use human reason alone, unaided by faith, to deduce the will of God from the natural order. As the creator of a system that defined human happiness in terms of a moral calculus based on pleasure and pain, Bentham was quite skeptical of all claims of religion. Thus it is not surprising that the results of Bentham's analysis of the influence of natural religion on human happiness are decidedly negative. Divided into two parts, Bentham first criticizes the major tenets of belief in a supreme being and its alleged benefits to humanity. Among these criticisms he notes the unreliability and incoherence of religion's promises of rewards or punishments after death, especially as an inducement to good conduct in this life; its generally fuzzy concepts concerning the character and will of God; and its inefficiency in preventing commonplace human evils. In the second part, Bentham catalogues the many ways in which natural religion harms both individuals and society as a whole: it taxes the individual's emotional well-being with the psychological burdens of fear, scruples, and guilt; prejudices the objectivity of the intellect; splinters society into contentious factions; and has other negative consequences which he details at length. At a time when the Anglican Church was still a highly influential institution in English society, it is easy to understand how this work would have been considered controversial. Some may still find it so today, and it remains an interesting challenge to traditional theism by a first-rate thinker.