Why You Can't Prove Tomorrow — Descartes to Nietzsche (Lecture 4)

Lecture 4 of "From Descartes to Nietzsche: The Birth of Science and the Death of God." In this lecture, Lee Braver unpacks one of the most striking arguments in the history of philosophy: Hume's problem of induction. Starting with the billiard ball thought experiment, Braver shows that we cannot reason our way from cause to effect without experience. But the truly shocking claim goes further. Even after a lifetime of experience, we still have no rational basis for expecting the future to resemble the past. Every attempt to justify that expectation ends up assuming the very thing it tries to prove, committing the logical fallacy of begging the question. So what saves us? Not reason, but custom and habit, the same mental machinery that drives Pavlov's dogs and Skinner's pigeons. Braver carefully distinguishes between being irrational and being arational, and explains how Hume uses these insights to draw firm boundaries around what human beings can legitimately claim to know, with devastating consequences for traditional philosophy. Watch the full lecture series:    • From Descartes to Nietzsche: The Birth of ...   About this course Lee Braver leads a tour through four of the most influential philosophers in Western history, asking a single question: how do we know anything at all? Beginning with Descartes, who rebuilt knowledge from scratch, the course follows Hume's challenge to cause and effect, Kant's claim that our minds shape the world we experience, and Nietzsche's confrontation with a universe drained of meaning. Across seven lectures, this introductory course traces one unfolding argument about truth, knowledge, meaning, and human freedom, showing how each thinker built on and challenged those who came before. About Lee Braver Lee Braver is a Courtesy Professor of Philosophy at the University of South Florida, where he was a Professor of Philosophy from 2012 to 2025. His interests include continental philosophy, especially Heidegger and Foucault, Wittgenstein, realism, and dialogue between continental and analytic philosophy. He is the author of A Thing of This World: A History of Continental Anti-Realism, Heidegger’s Later Writings: A Reader’s Guide, Groundless Grounds: A Study of Wittgenstein and Heidegger, Heidegger: Thinking of Being, editor of Division III of Being and Time: Heidegger’s Unanswered Question of Being and Introducing Ethics: A Beginner’s Guide Through Six Major Thinkers, as well as a number of articles and book chapters. Suggested reading Hume, D. (1993). An enquiry concerning human understanding (E. Steinberg, Ed.; 2nd ed.). Hackett Publishing Company. Chapters 00:00 The Problem of Induction 02:00 Cause and Effect: How We Know the World 04:47 The Billiard Ball Thought Experiment 07:44 Only Experience Teaches Causation 11:05 The Shocking Claim About Experience 13:42 The Future Will Resemble the Past: Or Will It? 17:57 Begging the Question: A Logical Fallacy 22:23 The Thanksgiving Turkey Analogy 24:18 Should You Eat Glass Tomorrow? 26:04 Custom and Habit Save Us From Reason 28:26 Pavlov's Dogs and Skinner's Pigeons 31:34 Humans Are Just Clever Apes 33:36 Arational vs. Irrational: A Crucial Difference 36:26 The Limits of What Humans Can Know Presented by Ergo, a nonprofit that publishes in-depth philosophy courses taught by leading scholars. Every course is freely available. https://ergo.org Connect with Ergo: Subscribe:    / @ergo_org   Instagram:   / ergo_org   LinkedIn:   / ergoorg