The very concept of objective truth is fading out of the world. Lies will pass into history.

—George Orwell

The book Post-Truth, by Lee McIntyre, opens with the above quote by George Orwell. Orwell, in fact, opens almost every chapter (although not chapter 5, which starts with a famous quote by Thomas Jefferson: “Don’t believe everything you read on the internet”). And one can almost see McIntyre as a scientific counterpart of the British essayist, trying to understand why we are nowadays in a situation where facts seem to be subordinate to our political point of view.

After introducing the concept of post-truth, the book discusses science denials, as they appear to be interesting groups to understand how post-truth survives. Doubt, he argues, is key. But not doubt in the sense that a skeptic might refer to. Doubt as a shield to keep your beliefs, your identity, protected from evidence. Take major tobacco companies, for example, and their effort to maintain that there was no conclusive link (i.e., no proof) of smoking leading to cancer. Funding junk research to cast doubt was all they needed to keep the truth from doing its job. Something clearly imitated in the recent years by climate change deniers.

But note that this is not reasonable doubt. One can be presented with plenty of scientific evidence—which most likely one won’t understand—suggesting that smoking causes cancer; but one needs just some uncertainty about this link to fall back to the complacent status quo position. Remember the debates on climate change, or creationism vs evolution? They are presented with two sides of the story, as if both had similar empirical validity. One is, then, ready to choose the most comfortable of the two. Yet only one is true.

The book goes in some detail about cognitive biases that can explain this propensity. Motivated reasoning, confirmation bias, the “backfire effect” and the “Dunning-Kruger effect” are some of the concepts linked to post-truth. It also discusses how the decline of traditional media and the rise of social media are key phenomena to understand how post-truth can thrive as it is doing nowadays.

McIntyre also mentions Postmodernism. This is a tricky topic, and it has been caricatured by the likes of Jordan Peterson. It is tricky because most of the Postmodernist movement was on the left, made up of progressives, yet the use of post-truth has mainly been on the right. But McIntyre does an excellent job—to be honest, the best I have ever read—in summarising the idea, how it evolved towards other disciplines, and how it relates to the conclusion that there is no such thing as truth.

A common criticism of linking Postmodernism to science denials and Trump is the fact that the supporters of the latter groups do not tend to read philosophy too much. They don’t know who Foucault, Derrida, or Rorty are. This is true. But, surprisingly, some of the ideologues behind these movements are wonderfully versed on Postmodernism. The idea that there are no truths but narratives resonates very well with the concept of alternative facts.

Lee McIntyre finishes discussing how to fight against post-truth. There is a lot of advice. One that I found particularly obvious but for some reason had overlooked. We have all heard this idea that one has to be aware of their own biases and try to correct them. There is no more powerful bias than confirmation bias. Residing in an echo chamber, rejecting to read or listen to certain opinions because you despise them is not only not neutral to the bias, but is actually reinforcing it. Reading broadly is, hence, key to combat post-truth. As it is, by the way, reading this excellent book.