Part 1: Truth and Skepticism

Part 1: Truth and Skepticism

Welcome! In this micro-course, we will grapple with the fundamental philosophical question of how we should decide what to believe. Our guides throughout will be Socrates and Descartes, the two most famous philosophical skeptics, as well as thinkers like William James and Blaise Pascal, who famously argues that we often have to believe “beyond the evidence” when seeking the truth in an uncertain world.

In this part, we will take a deep dive into skepticism and ask whether the most reasonable response to uncertainty is to simply refuse to believe anything at all. Throughout the course, we will ask what role logic and arguments should play, and how much you should depend on other people when figuring out what to believe.

Meet the Instructor

Paul Blaschko teaches philosophy at the University of Notre Dame and is an Assistant Director at the Notre Dame Institute for Advanced Study. Along with Professor Meghan Sullivan, he developed and designed God and the Good Life, an innovative “First Philosophy” course at Notre Dame. His research focuses mainly on the question of how we can be more responsible in forming beliefs.

Lecture 1: Refusing to Believe

In this part, Paul introduces “skepticism,” the ancient philosophical position that the best thing to believe if you care about the truth is… nothing at all.

Is Skepticism an Answer?

One of philosophy’s biggest questions is how we are capable of knowing reality. Or, put differently: Is the way things seem to us in the world the way they actually are?

To answer this question, we have to consider the possibility that we are actually just radically deceived or mistaken about what we think we know.

Rene Descartes was a philosopher who was deeply worried about the possibility that his worldview had been infiltrated by false beliefs. His solution, as counterintuitive as it might seem, was to come up with even more reasons to doubt what he had come to believe. Descartes used what he called the “method of doubt” in order to find a solid foundation on which he could build up a more secure worldview. Here is how the method works:

  1. Identify a belief or set of beliefs, like “I know that I have hands because I can see them.”
  2. Consider scenarios in which you might be radically mistaken about this belief, even though your evidence is exactly the same as it is now. For instance, if I were dreaming right now, it would look like I have hands, even if they had been removed under anesthesia while I slept.
  3. Allow these scenarios to induce skepticism about the original belief; admit that you do not really know what you thought you did.

Descartes applied this method over and over, for each of his beliefs, until his reached rock bottom — a “rational foundation” on which he could rebuild his worldview. For Descartes, this was the belief that he exists and thinks.

Even if we do not want to apply Descartes’ method in such an extreme way, we can use skepticism — and even his “method of doubt” — to improve our beliefs and worldview. For instance, take a belief that you hold, but that you are not that confident in, and ask yourself, “Where did this belief come from? Can I imagine believing this on the same evidence I have, even if it turned out to be false?” If the answer to the second question is yes, allow yourself to doubt the belief and use this doubt as a chance to reflect more deeply on whether you should keep it or go out and collect a bit more evidence.

Applying the Concepts: Skepticism and Politics

As we have seen, some philosophers think that skepticism is a way of making sure you are believing responsibly, but there are obviously ways of sowing doubt that are less than virtuous. In this video, we will consider some cases where skepticism is used to obscure the truth or to intentionally increase confusion, and we will ask whether this undermines the usefulness of this philosophical concept.

Activity: The Skepticism Assessment

In this activity, you are encouraged to take stock of how skeptical you are as a person. Then, you are given a chance to reflect on what this suggests about how you go about forming beliefs. Use this worksheet for your skepticism assessment.

Additional Resources


Click here for reflection and discussion questions on “What Makes a Life Good?” 

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