A third example of his anticipation of twentieth-century thinking is the line taken in his unpublished writings on homosexuality. Blackstone in his Commentaries had placed sodomy under the heading of 'Offences against the safety of individuals'. Bentham, writing in the 1770s, observed: 'How a voluntary act of this sort by two individuals can be said to have any thing to do with the safety of them or any other individual whatever, is somewhat difficult to be conceived' (UC lxxiv 5). The law which made sodomy a capital offence, he suggested, was based partly on the authority of St Paul, and partly on an irrational antipathy such as lay behind the ostracism of albinos by certain Red Indian tribes. The only contemporary argument in favour of the law which seemed to him to deserve consideration on utilitarian grounds was the argument that if homosexuality were legalized there would be a decline in population. But he said in 1816 that it would be unlikely to have any such effect (as the experience of classical Greece indicated), and that if it did have this effect it would be a good thing rather than a bad, since over-population was the cause of much of the misery that existed in the civilized part of the globe. Into the scales against the existing law he put the real injuries to human happiness that resulted from it, including the actual punishments inflicted and the fear of such punishments, the repression of sexual instincts on the part of homosexuals, and the vulnerability of such people to blackmail: 'how easy it is to fabricate out of the dread of an accusation of this nature an instrument of extortion is but too obvious' (UC lxxiv 183).
(John Dinwiddy, Bentham, Past Masters, ed. Keith Thomas [Oxford: Oxford University Press, 1989], 110-1)