Knowledge and Belief

For the majority of my life, I had a difficult time with the distinction between “knowledge” and “belief”.  It seemed to me for a long time that they were simply two words for roughly the same thing.  Both – more or less – refer to the conviction that a mental model matches objective reality.

I’ve never been to Turkmenistan.  As far as I can recall, I’ve never met anyone who has claimed to me that they’ve been there.  I’ve seen it on maps, read the name on occasion in books and articles, and heard about it on news stories perhaps a handful of times in my life; but the fact is that the country of Turkmenistan and I have had almost no interaction or points of contact throughout my life.  So, do I know that Turkmenistan exists, or do I believe that it exists?

Trying to clear up the terms, a common distinction that I rejected early on is that knowledge is a subset of belief defined as “justified, true belief”.  If my belief is not justified or turns out not to be true, then it’s not knowledge.

I reject this definition primarily because it means that the word “knowledge” isn’t something you can ever reasonably use.  While I tend to find the hard solipsist position functionally unhelpful, I can’t help but agree with the fundamental premise that we truly cannot know anything beyond our own existence (in some unknown form) and that we cannot help but assume the fundamental laws of logic.  There is always at least an imaginable scenario in which anything else we claim as knowledge is in fact not true.  I could conceivably be a “brain in a vat” or “plugged in to the Matrix” and simply never learn otherwise.

Beyond that, it doesn’t leave much room for “belief” as a usefully distinct word either.  If I am aware something isn’t true, then I don’t believe it.  If I am shown – by myself or by others – that can’t justify a belief I hold, I will cease to believe it and will instead hold a null position.  I may also potentially hold a belief that that acting as if one or another hypothesis is true is the best approach until such time as the hypothesis can be justified or a competing hypothesis provides justification for believing it, however that itself a separate belief and not strictly contingent on the justification or truth value of the first.

Ultimately, this leads back to both “belief” and “knowledge” being some kind of nebulous terminology between which I couldn’t meaningfully make a clear distinction.

This definition is often stated in discussions on philosophy as being equivalent to the statement that knowledge is objective truth whereas belief is subjective truth. This is intended to clarify the definition of justified, true belief and provide context by which people can orient their understanding of it. I however find it to be even more troubling both in that I don’t see how the definition can be reasonably stated that way and in that my definition of “truth” is “that which comports to objective reality” and thus renders the very concept of “subjective truth” as oxymoronic.

In more recent years, I’ve come to an uneasy and weak distinction for my own usage, which in practice seems to comport to how others use the terms even if they’re not thinking about it specifically.  In this distinction, “knowledge” is still a subset of “belief”, but it’s now defined as those beliefs for which I cannot currently provide any reasonable hypothesis against.  It’s a weak distinction because it relies on both on my own understanding of other information in order to build hypotheses and on my own ability to determine whether or not these hypotheses are reasonable.  Nevertheless, it’s a functional description for the moment.  It leaves me able to describe not only that I “know” something or that I “believe” something but even provides a framework for the strength of the belief based on the reasonableness of the alternative hypotheses that I can build.  Under that definition, “knowledge” is simply a belief where a specific threshold of reasonableness has been crossed and I consider all hypotheses against the belief to be “entirely unreasonable” given the set of other information that I have at my disposal.

Accordingly, I’d say that I know Turkmenistan exists, despite not having been there and the lack of other points of contact with it throughout my life.  The hypotheses that I can form for it not existing require pointless global conspiracies at a minimum or Matrix-like constructed realities at the more extreme end.  I don’t consider any of these hypotheses to be even remotely reasonable and thus I claim I have knowledge of Turkmenistan’s existence.

I contrast that with the fact that I believe my wife is currently at home while I write this but I do not know that.  I’m sitting on a train, travelling at nearly 200km/h towards the city of Frankfurt am Main and my home is in the village of Moritzburg, near the city of Dresden.  My wife was at home when I left and I wasn’t aware of any plans she had to be somewhere else, but I can easily conceive of a large number of perfectly reasonable and normal scenarios in which she’s not.  She may be visiting friends; she may have gone for a walk; she may have taken our kids to the playground.  Given the weather isn’t great and that I’m not aware of any plans, I think it’s more likely that she’s at home and thus I believe that to be the case, but I certainly don’t know it.