I think my chain falls of on the idea that we can assign reliable probabilities to various hypotheses, prior to our own thorough investigation of the available scientific material.
Yep! We do it all the time! How likely do you think it is that the city of New York has just been destroyed by a nuclear blast? That your parents are actually undercover agents sent by Thailand? That there is a scorpion in the sandwich you’re about to eat? Most people would consider those extremely unlikely without a second thought, and would not feel any need for a “thorough investigation of the available scientific material”. And that’s a perfectly sensible thing to do!
Knowledge in what sense? In the sense of “justified true belief” as some philosophers like to define knowledge? No, but that’s a really bad notion of knowledge because pretty much nothing can be justified in the sense that such would insist upon. Can you assign really high degrees of certainty to the conclusions? Yes. If that’s what knowledge is then yes, it is knowledge.
It may help to note that Bayesianism (the form of epistemology most popular at LW) rejects the entire idea of justified true belief or anything similar to it, and only talks about degrees of certainty, but I think you already know that.
Yep! We do it all the time! How likely do you think it is that the city of New York has just been destroyed by a nuclear blast? That your parents are actually undercover agents sent by Thailand? That there is a scorpion in the sandwich you’re about to eat? Most people would consider those extremely unlikely without a second thought, and would not feel any need for a “thorough investigation of the available scientific material”. And that’s a perfectly sensible thing to do!
Indeed it is perfectly sensible from a pragmatic point of view.
But is it actual knowledge?
Knowledge in what sense? In the sense of “justified true belief” as some philosophers like to define knowledge? No, but that’s a really bad notion of knowledge because pretty much nothing can be justified in the sense that such would insist upon. Can you assign really high degrees of certainty to the conclusions? Yes. If that’s what knowledge is then yes, it is knowledge.
This is an interesting “rebuttal” to the goal of defining “true knowledge”. I’ll have to think more about this.
It may help to note that Bayesianism (the form of epistemology most popular at LW) rejects the entire idea of justified true belief or anything similar to it, and only talks about degrees of certainty, but I think you already know that.
Related articles:
How to Convince Me That 2 + 2 = 3
Infinite Certainty
0 And 1 Are Not Probabilities
tl;dr: 100% probability = ∞ evidence; you really don’t have it