Social justice, genomic justice, and the veil of ignorance: Harsanyi meets Mendel

John Harsanyi and John Rawls both used the veil of ignorance thought
experiment to study the problem of choosing between alternative social
arrangements. With his ‘impartial observer theorem’, Harsanyi tried to
show that the veil of ignorance argument leads inevitably to utilitarianism,
an argument criticized by Sen, Weymark and others. A quite different use
of the veil-of-ignorance concept is found in evolutionary biology. In the celldivision process called meiosis, in which sexually reproducing organisms
produce gametes, the chromosome number is halved; when meiosis is
fair, each gene has only a fifty percent chance of making it into any
gamete. This creates a Mendelian veil of ignorance, which has the effect
of aligning the interests of all the genes in an organism. This paper shows
how Harsanyi’s version of the veil-of-ignorance argument can shed light on
Mendelian genetics. There turns out to be an intriguing biological analogue
of the impartial observer theorem that is immune from the Sen/Weymark
objections to Harsanyi’s original.