How Do You Know? A Dialogue

Gordon Barnes | 2021
Posted in: Bridging Divides Epistemology
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Key points:

It is helpful when thinking about the key points or big ideas presented in this book to look at the chapter titles. Chapter 1: Where Are the Experts? is devoted to a discussion of whether it is possible for a non-expert to know if someone else is really an expert, and how to know when you should trust the testimony of another person. That leads to a discussion of bias in Chapter 2: They’re All Biased! which discusses the reality and relevance of bias, both to trust in others and trust in oneself. Chapter 3: I Read It on the Internet explores how the Internet has affected us as knowers, leading to a discussion of conspiracy theories. Chapter 4: We Still Disagree considers the issue of disagreement between equally intelligent & well-informed people. The book closes with a discussion of the problem of moral knowledge in Chapter 5: Knowing Right and Wrong.

What resonated with me:

I found the dialogue technique the author used to discuss these topics to be incredibly helpful. What jumps out at the reader more than anything else is the process — by presenting the topics in the form of a dialogue, the author models what a civil discussion could (and, I would suggest, should) look like. 

He does this by introducing three characters: two friends who grew up together and came to college with very like-minded ideas but then grew apart when they reacted differently to the information they acquired in their college classes, and a third friend who plays the role of a mediator of sorts. What this does is create multiple opportunities for listening — a habit largely lacking in much of today’s discourse. And the use of this technique keeps the reader engaged, as it avoids the dryness of a lecture and brings what could otherwise be perceived as a very academic discussion into the real world.

Another quality of the book that lends it much-needed relevance and authenticity is the author’s choice of timely topics: for example, I can’t think of a more current topic than the one introduced in Chapter 1: the safety and reliability of the science behind vaccines (via a debate between the characters about whether they cause autism). And the effect of the Internet on our knowledge and discourse (the topic of Chapter 3) is a discussion long overdue. 

However, my favorite chapter in the book is probably Chapter 2, which explores the concept of bias. Few of us truly understand how bias works or that no one is immune from its effects. This chapter not only educates the reader about bias; it also offers strategies the reader can use to counteract their own biases.

In short, this timely and very readable book brings the much-needed tools of critical thinking and civil discourse to the masses in a very practical and down-to-earth manner that I believe will be appealing to a wide variety of individuals, from all walks of life. The reader walks away knowing about epistemic bubbles, collaborative thinking, epistemic peers … and much more. And perhaps, in the process, they have learned, at the very least, how to remain civil in a very uncivil period of time.


In the interest of full disclosure, Gordon is my younger brother. To give you just a bit of background: I am the second eldest of a family with six siblings; Gordon is the fourth eldest. There is a large age difference from the oldest (62) to the youngest (42), and an even larger disparity in political and religious views. I say that to say this: in our family, we have struggled mightily not to let the current polarity in our country negatively affect our family relationships. Sibling relationship aside, I believe Gordon has written a book that is incredibly timely for the time in which we live — and he and I do not always see eye to eye!