Ever since Aristotle's famous argument about the sea-battle tomorrow, there has been intensive and controversial discussion among philosophers whether the truth of statements about the future leads to determinism. Ther e is controversy about Aristotle's own solution to the problem, as well as the views of classical and medieval commentators on Aristotle. Seel's book attempts to answer this question for the Neoplatonist Ammonius (5th-6th century AD). In so doing, he also opens up new insights into Neoplatonic thought.