How did Philo of Megara’s view of conditionals differ from Diodorus Cronus’s view?

Philo of Megara and Diodorus Cronus held differing views on the truth conditions of conditional propositions:

• Philo of Megara: He defined a conditional as true if and only if it does not currently have a true antecedent and a false consequent. This interpretation corresponds to the modern concept of material implication. Because this definition relies on the current state of the propositions, Philo believed that the truth value of a conditional could change over time.12

• Diodorus Cronus: He argued that a conditional is true if and only if it is, and always was, impossible for the antecedent to be true while the consequent is false. Under his framework, a true conditional must hold across all times—past, present, and future. Consequently, for Diodorus, a conditional’s truth value is fixed and cannot change over time.12