Sunday, 5 April 2020

Concerning Knowledge Part 2

The study of knowledge is known as epistemology. In the previous two posts I discussed an argument for the existence of God in which I suggested that the existence of Truth (where the Truth is the set of all true propositions) justifies the idea that an omniscient knower exists. I suggested that a person's beliefs are true when they align with the beliefs of this omniscient knower. In tonight's post I wish to set this argument aside and talk about knowledge more generally. I wish to discuss the Gettier problem again. And I also wish to show that any naive understanding of the nature of knowledge is defective because it fails to take account of the fact that most knowledge is acquired through direct or indirect interactions with other knowers.

A traditional definition of knowledge, first presented but not ultimately endorsed by Plato, is that knowledge is true, justified belief.  That is, for a given proposition to count as knowledge, it must be true, it must be justified, and it must be believed. Edmund Gettier raised an objection to this simple definition – I discussed the Gettier problem in the previous post and I direct the reader, if he or she is interested in it, to the article in Wikipedia about it. We can summarise the Gettier problem in the following way.

1. Smith believes P.
2. Smith believes Q.
3. P implies Q.
4. P is false.
5. Q is true.

Therefore Smith has a true justified belief in Q but it can't count as knowledge because the justification for is false. Smith believes Q. Q is true. And is justified. But it still isn't knowledge. The Gettier problem has stirred up a lot of debate among professional philosophers but the obvious solution, the solution I discussed in the previous post, receives little mention in Wikipedia. I know that I am not the first to consider this obvious solution and wonder if the compilers of Wikipedia. the lexicographers in charge, downplayed this obvious solution in favour of less persuasive solutions to encourage readers to work it out for themselves. Alternatively it could be that many of the people who call themselves philosophers are all stupid. This wouldn't surprise me.

Before I move on to presenting the obvious solution, I need to bring up a semantic issue. There is no word in English for a unit of knowledge. There is a neologism 'knol' associated with knowledge which I shall appropriate for my own purposes in this essay. A 'knol' is a proposition that is known by a subject.  Although I would like to avoid using this word 'knol' in this essay, it may be necessary, even though it is clumsy and I would have preferred it if the English language was furnished with a better word.

The solution to the Getier problem is that for a true justified belief to count as knowledge, to be a 'knol', the justification must also be a true, justified belief, must also be a 'knol'. I discussed one of Gettier's examples in the previous post. I shall now quote another:

"Smith, it is claimed by the hidden interlocutor, has a justified belief that "Jones owns a Ford". Smith therefore (justifiably) concludes (by the rule of disjunction introduction) that "Jones owns a Ford, or Brown is in Barcelona", even though Smith has no information whatsoever about the location of Brown. In fact, Jones does not own a Ford, but by sheer coincidence, Brown really is in Barcelona. Again, Smith had a belief that was true and justified, but not knowledge."

Obviously, the reason that Smith's belief that "Jones owns a Ford, or Brown is in Barcelona" doesn't count as knowledge, isn't a knol, is that the justified belief that "Jones owns a ford" is false. For a true justified belief to be a knol, the justification must also be a knol. The picture I wish to present of knowledge is that it is a vast interconnected web or network of true, justified beliefs, of knols. Every knol is justified by other knols which are themselves justified by other knols. Unfortunately, this picture conjures up the possibility of an infinite regress, something I think we should try to avoid. One way to banish the possibility of an infinite regress would be to suppose that knowledge is circular: (P is justified by and R. R is justified by S. S is justified by P.) Another way to banish the possibility of an infinite regress, a preferable way I believe, is to drop the requirement that knols require justification, to declare that some knols are true beliefs that don't need to be justified. According to this second strategy, knowledge consists of two different types of knol – those that are justified by other knols and those that do not require justification perhaps because they are self-evident or perhaps because they are generally accepted by everyone without anybody ever challenging them. Consider another example of a Gettier problem:

"After arranging to meet with Mark for help with homework, Luke arrives at the appointed time and place. Walking into Mark's office Luke clearly sees Mark at his desk; Luke immediately forms the belief "Mark is in the room. He can help me with my logic homework". Luke is justified in his belief; he clearly sees Mark at his desk. In fact, it's not Mark that Luke saw; it was a marvelous hologram, perfect in every respect, giving the appearance of Mark diligently grading papers at his desk. Nevertheless, Mark is in the room; he is crouched under his desk reading Frege. Luke's belief that Mark is in the room is true (he is in the room, under his desk) and justified (Mark's hologram is giving the appearance of Mark hard at work)." But it isn't knowledge. Luke's belief that Mark is in the room isn't a knol even though it is both true and justified.

We can parse this example in the following way. Luke has the belief that Mark is in the room. This belief is true. This belief is justified by the Luke's perception of seeing Mark at his desk grading papers. This perception is false. However, this perception (or belief) is also justified: it is justified by the anterior belief shared by all people that sense perceptions are trustworthy. This knol ("My sense perceptions are reliable") is a knol that everyone accepts without justification, as being axiomatic. In this case it is wrong. But generally speaking such a knol, the knol that sense data is trustworthy, is fundamental to the way we make sense of the world.

So, in order to resolve the Gettier problem without assuming an infinite regress, we must suppose that some knols are true justified beliefs while other knols are simply true beliefs. We can distinguish between these two different types of knol by calling the first kind 'justified knols' and the second 'bare knols'. We might suppose that most of the knols that constitute a person's knowledge-network are of the first kind, that bare knols are like the fundamental axioms of arithmetic and the bulk of a person's knowledge consists of justified knols. But this isn't true. Most of the 'facts' that a person knows are justified by nothing whatsoever.

Consider the following example. "Earth is the third planet from the Sun". You know this and I know this. But is this belief justified? If I ask you why you believe Earth is the third planet from the Sun, you will be forced to say something like, "Someone told me it or I read it somewhere when I was a child." But you will be unable to name and cite your source. Likewise, you and I both know that an effective method to kill viruses on surfaces is to wipe the surfaces down with disinfectant. But this knol is justified, if it is justified at all, by inductions from our observations of others doing this. Although you may have been told explicitly that disinfectant kills viruses, I haven't, or if I have, have forgotten it. This raises the possibility that some of our knols are based on justifications that we have since forgotten. Can we be said to have a true, justified belief if we can no longer remember the justification for our belief?

I don't know if I have ever said this explicitly in this blog, although I think I must have, but I strongly feel that much of our knowledge of the world is derived from what we learn from others – from books, newspapers, conversation with friends and family, Wikipedia. This conviction, that much of our understanding of the world derives from hearsay, deeply informs my philosophical thinking. It puts me at odds with both the Empiricist and Rationalist traditions. Empiricists, I think
like Hume and definitely like Ayn Rand, hold that our knowledge of the world is based on our experience of the world. What we know about cats we know from our observations of cats in the real world. A strong Rationalist, however, might subscribe to the Platonic notion that we have an innate understanding of cats, that we are born with some understanding of the 'cat' Idea. I think I think that most of our knowledge is gained a posteriori but is learned indirectly, through language. I know that cats predate viciously on native birds not because I have observed them doing it or because I somehow worked it out rationally but because I have been told they do so by the media. I have never observed a neutrino and certainly could never arrive at the concept of a neutrino through reason alone; rather, I read about neutrinos in my physics textbook and have chosen to place my trust in the book's authors. Did Russia intervene in the 2016 American Election in support of Trump? I could choose to believe Fox, or I could choose to believe Nancy Pelosi and Bill Maher. Not only do we learn about the world from others, when there is differences in what people report, we must decide who to believe. I think we live in a world where there is a crisis in our collective notion of truth because misinformation spreads so easily through social media. There have always been kooks and conspiracy theorists but we live in an age where the lunatic fringe has had its voice amplified.

Something which factors into my understanding of truth is my own experience of mental 'illness'. I have experienced delusions, a long time ago. When I first became 'sick' in 2007, I formed the delusion that the world was ruled by a conspiracy of closet homosexuals. The aspect of this delusion that is interesting here is that it was unfalsifiable – there was no way I could 'reality test' it. No member of the conspiracy could be expected to blow the whistle on it; those who threatened to do so were either killed or were outed as gay and in this way destroyed. The lesson I eventually learned is to be skeptical about all my beliefs. In order to recover, and I have been recovered for a long time now, I had to dismantle all my delusions. And I had to realise that psychiatric discourse is itself insane, delusional. This is something that it is necessary for me to talk about and maybe I will in the next post.

In conclusion... In this post I have presented two somewhat different pictures of knowledge. One picture is that knowledge is a web or network of interconnected true, justified beliefs, in which every belief justifies other beliefs and is justified by other beliefs. The second picture is knols can be discreet separate factoids that we learn from a trusted source. Which picture is right? Perhaps a combination of the two. I like Bill Maher and sometimes I agree with him but sometimes (especially when he talks about Israel) I don't. When assessing truth claims we assess, compare, consider, evaluate. It is an extraordinarily complex process. This post is quite long enough now: the subject of knowledge is so big that to do it justice we might need to write ten books about it. And I haven't finished talking about it yet.

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