Only Donald Trump could have a justified true belief that doesn’t count as knowledge

In case you are sick of invoking the generic characters “Smith” and “Jones” to explain the Gettier problem, the famous challenge to the idea that knowledge is justified true belief, Donald Trump provided an alternative illustration recently.

For millennia, knowledge was thought to be justified true belief. If you have good reasons for holding a belief (it is justified), and that belief is correct (or true), then that belief counts as knowledge. This intuitive and straightforward account of knowledge can be found as far back as Plato, and pretty much everyone agreed with it. Until Edmund Gettier, that is, and the publication of his article “Is Justified True Belief Knowledge?

In this paper, whose infamy is only bolstered by the fact that it is a mere three pages long, Gettier gives two counterexamples to the “justified true belief” account of knowledge. I won’t get into the amusing details of the counterexamples (because the details I am about to give from Trump’s unwitting demonstration of the problem are amusing enough), but the basic point of them is to show that even a belief that is both justified and true can still fail to constitute knowledge.

And this brings me to Donald Trump. A week or so ago, when meeting with the Spanish foreign minister, he suggested that Spain should build a wall across the Sahara desert to keep migrants and refugees out of the country. When the vastness of the Sahara desert was pointed out to Trump, he replied: “The Sahara border can’t be bigger than our border with Mexico.”

Based on the context of the exchange between Trump and the Spanish foreign minister, it appears that Trump believes that Spain’s border with the Sahara is far smaller than the US border with Mexico. As it happens, this is true, since Spain has two small enclaves in North Africa, and the combined length of their borders with the Sahara is nowhere near the length of the US-Mexico border. And the belief is arguably justified simply by virtue of the fact that Spain is far smaller than the US, and thus its border with any country (or discrete territory, like the Sahara) must be smaller than the US border with Mexico.

However, it is doubtful that Trump possessed knowledge in this instance. It is hard to believe that Trump is even aware of the small enclaves of Spanish territory in North Africa, and so his supposition is based on ignorance of the size of the Sahara and of the fact that the Spanish mainland is on a different continent. His belief is right and (at least arguably) justified, but for the wrong reasons. He is accidentally right. And this is precisely the epistemic phenomenon that the Gettier problem is designed to call our attention to.

So, Trump is right not because of the facts, but in spite of them.