Gettiers in software engineering (2019)

Physics has kinda-solved what it means to know something.

- JTB is not enough, for something to be “true” it needs _testability_. In other words, make a prediction from your knowledge-under-test which would be novel information (for example, “we’ll find fresh cow dung in the field”). - nothing is really ever considered “true”, there’s only theories that describe reality increasingly correctly

In fact, physics did away with the J: it doesn’t matter that your belief is justified if it’s tested. You could make up a theory with zero justification (which doesn’t contradict existing knowledge ofc), make predictions and if they’re tested, that’s still knowledge. The J is just the way that beliefs are formed (inference)

"Testability" to me sounds like a type of "justified" - I can be justified for many reasons, and testability is just one of those. But there are reasons where I might be justified but where testability is impossible.

For example, if I toss a coin and it comes up heads, put the coin in my pocket and then go about my day, and later on say to somebody "I tossed a coin earlier, and it came up heads", that is a JTB, but it's not testable. You might assume I'm lying, but we're not talking about whether you have a JTB in whether I tossed a heads or not, we're talking about if I have one.

There are many areas of human experience where JTB is about as good as we are going to get, and testability is off-limits. If somebody tells me they saw an alien climb out of a UFO last night, I have lots of reasons to not believe them, but if this a very trustworthy individual who has never lied to me about anything in my decades of experience of knowing them, I might have a JTB that they think this is true, even if it isn't. But none of it is testable.

Physics - the scientific method as a whole - is a superb way to think about and understand huge swathes of the World, but it has mathematically proven limits, and that's fine, but let's not assume that just because something isn't testable it can't be true.