All you are doing here is taking the form of our external relation to your previous example and inserting it into a new example as part of its internal structure. Here, however, the relation is not between a “real” situation and a hypothetical one but between two points in time inside the example itself.

I'd like to try another example. (I want to try to bring out how the distinction between truth and justification matters in practical life.)

Suppose that you’re a civil engineer, and your entire job is to verify the strength and safety of a certain bridge. (It’s a massive and important bridge, you run various tests each day, let’s say.) Now, though you’re good at math, the calculations involved are so huge and complex that you rely on certain computer systems to collaborate your tests results.

One night, a crazed (but intelligent) madman bent on destroying the bridge puts a virus in your computer system. The virus makes your computers calculate that ‘everything is well’ (e.g., the strength of the steel is of degree X – where X is appropriate strength), even if everything is not well, i.e., even if the steel is actually weak, and far too weak for the safety of the bridge’s operations.

Having placed the virus, this genius madman gradually (and imperceptibly, from mere visual observation) weakens the bridge’s strength through application of (say) certain acids at certain steel joints.

After a few weeks of this (and throughout this time you work valiantly at your verification work), the bridge (to your total and appropriate surprise) collapses, killing over a hundred people.

Now, before the collapse, it seems correct to say

1. You (the civil engineer) were justified in believing that the bridge was safe.
2. The bridge was not safe. What you were justified in believing was not in fact true.

To bring (1.) and (2.) out clearer (in a practical way), the subsequent federal investigation into the bridge’s collapse should absolve you (the civil engineer) from any wrongdoing once they discover the foreign virus on your computer systems. In other words, you had done your best – you had no way to know about the virus – you were justified in believing what you did about the bridge’s safety. However, the very fact that the bridge collapsed due to weak steel joints means that your justified belief was not in fact true.

Does truth = justification in a case like this?

Internal to the example, there is no truth in the hypothetical situation even if we posit from our external viewpoint that such is the case: “common sense” therein dictates that we do not become true to it in our actions. In fact, to do so would be insane. It would defy common sense. It would be unjustified.

Now you'll recall that at the beginning of this discussion I indicated that 'truth' and 'justification' evolved within “separate lexical contexts.” A contemporary example of this can be found in the field of library and information studies with the terms 'cataloging' and 'metadata analysis'. Cataloging is metadata analysis, metadata analysis is cataloging — which is to say that, like truth and justification, their meanings are isomorphic and for the most part interchangeable. Even so, that hasn't prevented certain theorists from trying to pin down their semantic differences in terms of essences that transcend their separate genealogies, and to establish a systematic relationship between them within a single, overarching project.

On the question of “mattering”: it depends on who you ask and with respect to what event you want that person to be true to. A hypothetical situation is not an event. Its proposal, however, is. Thus I've been true to your example this whole time because it matters to me — i.e. it amuses me to have this discussion. But the hypothetical situation internal to that example cannot matter to me in so far as I am to obey common sense, least of all because no one has proposed it to me therein — unless of course you revise and qualify your example without justification, and in that sense defy the truth that has emerged between us.

As a different angle on the question, if 'justification is truth and truth is justification' what explains the fact that we have two terms here and not one? Further, why have a lot of people thought that these two terms apply in different circumstances? (Prima facie, it seems to indicate that there are two ideas floating around that are different…) What do you think explains this?

Above, you said that: “It amounts to a disjunction between what, from a perspective internal to the example itself, is purely hypothetical and what the evidence (my reliable friend's testimony) actually points to.”

I'm assuming that that which 'is purely hypothetical from the perspective internal to the example' is 'truth' and 'what the evidence actually points to' is 'justification'.

I won't here contest this way of making the distinction, but instead ask… Isn't that a real distinction that makes a difference? Isn't it the case that purely hypothetical things matter? Doesn't 'truth' matter?

Surely it makes a difference if one of our hypotheses is wrong? (Indeed, don't we revise our beliefs? Why else would we do this unless we have falsified one of our hypotheses?)

Justification evokes the logic of “justifying one's actions,” of aligning it with an original act or “event.” For a belief to be justified it must conform with or “be true to” that event. Justification is truth, truth is justification.

Evidence is only a tool to provoke conformity, to provoke truth.

Does he know it truly?

Truth evokes the logic of “being true to” something that emerges subjectively.

1) “common sense” is nothing more than failure to actually think (try using “common sense” about what appeals to “common sense” actually ask you to do… wait, better yet just think about what it means to argue from “common sense”).

2) Badda being, just start some other discussion. Hell I'll even join in, but don't, DO NOT do the matrix crap that horrible professors have all been condemned to do because of pop philosophy that would have us substitute actual thought for shit like “common sense.”

“I know that it snowed yesterday in my friends backyard.”

Because that's the right thing (the justified thing) to believe in the circumstance.

Further, if it in fact had snowed yesterday, then you would indeed know the relevant fact.

But you can't know something that isn't true.

You'd be right to claim you know. The case is simply one where, though you're right to claim you know, in fact you don't have knowledge (because the belief isn't true).

(Sometimes we don't necessarily use 'knowledge' (the word) in this way. Sometimes I say someone has knowledge just in case he has really justified beliefs about a certain discipline – “he knows his stuff”, for example – or something like that (compatible with each belief in fact being false). But we shouldn't let words distract us more than it takes to disambiguate them. Philosophers (at least the analytic ones) aren't concerned with that sense of 'knowledge', it isn't as interesting as the sense that picks out that intriguing state of being rightly in touch with the truth. – We want our beliefs to be true, right? – )

So clearly, since indeed your friend could have briefly forgot the day (or whatever), and since it is clearly possible that she tell you what she did despite the fact that it actually didn't snow in her backyard yesterday…the case remains one where you are justified, but in which your belief, nevertheless, is not true.

Doesn't make them true though.

I'm curious what you think of The Matrix. When you saw the movie (if you haven't, watch it!), what did you think about the ordinary empirical beliefs Neo likely had even while Matrix-trapped? Were they true?

“I know that it snowed yesterday in my friends backyard.”

Because that's the right thing (the justified thing) to believe in the circumstance.

Further, if it in fact had snowed yesterday, then you would indeed know the relevant fact.

But you can't know something that isn't true.

You'd be right to claim you know. The case is simply one where, though you're right to claim you know, in fact you don't have knowledge (because the belief isn't true).

(Sometimes we don't necessarily use 'knowledge' (the word) in this way. Sometimes I say someone has knowledge just in case he has really justified beliefs about a certain discipline – “he knows his stuff”, for example – or something like that (compatible with each belief in fact being false). But we shouldn't let words distract us more than it takes to disambiguate them. Philosophers (at least the analytic ones) aren't concerned with that sense of 'knowledge', it isn't as interesting as the sense that picks out that intriguing state of being rightly in touch with the truth. – We want our beliefs to be true, right? – )

So clearly, since indeed your friend could have briefly forgot the day (or whatever), and since it is clearly possible that she tell you what she did despite the fact that it actually didn't snow in her backyard yesterday…the case remains one where you are justified, but in which your belief, nevertheless, is not true.