Monday, June 06, 2005

What is the difference between knowledge and true belief?

Posted by AmishThrasher at 5:47 pm
He knew a lot of stuff...
To answer this question, we will look at what true beliefs are, and why (in themselves) they are not knowledge. Then we will then look at a modified causational account and point out the differences.

Firstly, we need to ask what true beliefs are, exactly? True beliefs are the building materials that most accounts of knowledge are built out of; however they are not (in themselves) knowledge. To continue this metaphor, if you imagine knowledge as a modern western style building, true beliefs are like concrete, steel, bricks, timbre and stone. While most western style buildings utilize these materials, you would feel short changed if you asked a builder to build you a house, and all you got was a pile of bricks.

In themselves neither beliefs, nor truths, are knowledge. I can believe that Lee Harvey Oswald shot JFK, but it’s clearly not true; I don’t know that Lee Harvey Oswald killed JFK. It turns out that a hit man hired by J. Edgar Hoover and Lyndon Johnson was behind the grassy knoll on that fateful Dallas day. I don’t know Hoover and Johnson were co-conspirators if I believe Lee Harvey Oswald was the killer.

And true beliefs (combined) are different to knowledge too. Imagine, for instance, I were writing an essay for philosophy. As an example, I choose the JFK assassination, and out of everyone that has been suggested to have been conspiring to assassinate Kennedy (CIA, KGB, Right wing militia groups, the mafia, etc.), I chose J. Edgar Hoover and Lyndon Johnson. I form the belief that an ambitious Vice President and a paranoid FBI head co-conspired, and it turns out (by chance) that I guessed correctly. I had, at the time of writing the aforementioned example, no way of knowing for certain that was the case; thus I had a true belief but didn’t know.

So what does the causation account add to make true beliefs into knowledge?

The causal account adds: The fact that p causes S’s belief in p(1). Goldman(2) added to this theory his account of deviant causal chains. He claimed that the fact that p causes fact that q (which can be mistaken by S as a just belief in p) does not amount to S having knowledge of p. However, if S is aware of the causal connection between p and q, and has a belief in q, from which p is inferred, S does have knowledge.

This causal account does have two big problems though(3). The first is knowledge of the future, and the second, non-causal knowledge (for example, mathematics). My immediate response would be to say that different kinds of knowledge are necessary in these cases. A causing B is, at best, inductive knowledge(4), and so the causal account deals with inductive knowledge. Which means that we need different understandings for the future, and for deductive knowledge.

It’s easier to be sceptical about the future than the past or present. When we say that we *know* something will happen in the future, can we know it in the same way that I know I’m currently typing this on an iMac? Or that last night the dog was sleeping on a chair that he wasn’t allowed to? The English language is littered with clichés like “You’ll never guess what’ll happen next”, “You never know what the future holds”, “... has an uncertain future”, “A cloud of uncertainty hangs over...”, etc. We often gain pleasure from not knowing future truths; imagine while reading a great novel, someone says ‘Oh, *that* book, yeah she dies in the end to save her sister’, it spoils the ending because you now have a strong belief in what you will read at the end of the novel. What, at first, appears to be an anomaly of the theory is really an insight.

I can list 10 things, which I didn’t expect to happen the day before, yet I know happened to me yesterday. I can list 10 things, which I didn’t expect to happen the day before, yet I know happened to me today. Yet it seems contradictory to say that I can list 10 things, which I don’t expect to happen the day before (i.e. today), yet I know will happen to me tomorrow. And saying that future truths are fixed at all certainly seems to have further philosophical implications, for example destiny.

Consider a team, over 100 points up in the Grand Final, with 10 seconds to go. It is not humanly possible to score 100 points in 10 seconds, even if the winning field left the arena. It would be safe for some to say they know that the winning team will win. Unfortunately for them, and the winning team, a sudden and unexpected earthquake levels the MCG with 5 seconds to go - and does. The match is never finished.

So what we mean when we say “I know y will happen tomorrow” is something like “I strongly believe y will happen tomorrow”; with some justification. And when we say “I knew y would happen”, what we mean is “Prior to y happening, I held a strong belief that y would happen, and by chance it did”. In both cases, we are talking about ‘prediction’ rather than ‘knowledge’. Equivocation means “…an argument may be cogent, but only if some word or phrase is interpreted in the same way throughout; and its premises may be true, but only if that word or phrase is interpreted differently in different places”(5). Talking about prediction in the same sense of other kinds of knowledge is equivocating.

Having tied up the loose end of knowledge of the future, the question becomes “What about 1 + 1 = 2”? This is where we could adopt a belief in q (from which belief in p is inferred) is knowledge, so long as S is aware of the causal chain, should come into play. In this case though, there are multiple q’s. Q1 is the truth that a + b = c - if true - is a deductively valid mathematical form, Q2 is the belief that a and b are true, Q3 is the truth S has added a and b correctly; Q4 is the truth that a and b both equal 1. Based on Q 1 - 4, we know that 1 + 1 = 2, and any claim that C is different is contradictory.(6) The important factor in this causal chain, adapting the causal account to deal with deductive truths is Q1; the fact that Q1 is deductive. And we know Q1 because there is no possible non-contradictory world where Q1 isn’t true. So, dealing with deductive knowledge, Q1 -> Q4 causes knowledge that P.

In conclusion, what is the difference between true belief and knowledge depends on the type of knowledge. For inductive knowledge, you need to add the extra premises of Goldman’s(7) causational account. Future knowledge is prediction, not knowledge. For deductive knowledge, we need to make sure we know certain kinds of knowledge are deductive as part of the causal chain; we take Goldman’s account, and add some extra premises relating to deductive knowledge.

(1) Oakley, Tim, PHI21CAS Lecture, Monday March 15th, 2004, Bundoora, La Trobe University.
(2) Oakley, Tim, PHI21CAS Lecture, Tuesday March 16th, 2004, Bundoora, La Trobe University.
(3) ibid.
(4) Phillips, Ross and Oakley, Tim, “Reason &Argument”, February 1996, Monash Philosophy, p. 35.
(5) Op. Cit., pp. 23-4.
(6) Op. Cit., p. 34.
(7) Oakley, Tim, PHI21CAS Lecture, Tuesday March 16th, 2004, Bundoora, La Trobe University.