Soon after the first law of thermodynamics was postulated in the mid nineteenth century, it was realized how the law presupposed a more elementary law, which we now call the zeroth law ... But scientists soon realized how even the zeroth law was too advanced, since it presupposed a yet more elementary law, which explains why the minus-oneth law had to be formulated. —Paul M. S. Monk, 2008. "Laws and the minus-oneth law of thermodynamics", in Physical chemistry: understanding our chemical world, p. 8.