 Already Aristotle (384–322 B.C.E.) was aware of the problem of future contingents. Chapter IX of his work, On Interpretation, is without doubt the philosophical text which has had the greatest impact on the debate about the relations between time, truth, and possibility. The discussion in this text certainly bears witness to the fact that Ancient philosophy was highly conscious of tense-logical problems. Central to the discussion in this famous Aristotelian text is the question of how to interpret the following two statements: