Why did William of Ockham consider logic essential to every science?

William of Ockham regarded logic as the fundamental and indispensable science for practicing all other disciplines, including the study of God, the natural world, and human institutions.1

His commitment to logic stemmed from his view of it as the "science of terms," which provided the necessary tools for rigorous analysis and clear reasoning. Throughout his career, Ockham utilized logic as his primary weapon in disputes, insisting on evaluations that were strictly rational, focused on clear distinctions between the necessary and the incidental, and differentiated between evidence and degrees of probability.1

By emphasizing logic, Ockham sought to eliminate unnecessary entities and assumptions—a principle of economy famously known as Ockham’s razor—thereby ensuring that scientific and theological explanations remained grounded in reason rather than superfluous metaphysical constructs.213