Abstract

This paper offers a novel argument for fatalism: if one accepts the logical possibility of fatalism, one must accept that fatalism is true. This argument has a similar structure to the ‘knowability paradox’, which proves that if every truth can be known by someone, then every truth is known by someone. In this paper, what I mean by ‘fatalism’ is that whatever happens now was determined to happen now in the past. Existing arguments for fatalism assume that the principle of bivalence holds even for future propositions, that past truths are necessarily true, and/or that possible propositions never change into impossible propositions. However, my argument does not assume such premises. It assumes only the logical possibility of fatalism. Here, what I mean by ‘fatalism is logically possible’ is that there is at least one possible world where whatever happens now was determined to happen now in the past. Since this assumption is weak (thus is plausible), I believe it to be much stronger than the existing arguments for fatalism. In addition, I also show that what will happen in the future is determined now.