I saw the term JTB (Justified true belief). What is the act of Justificaton ? What makes somthing "Just" ?

Cheers Sharon

closed as off-topic by Keelan, Dave, virmaior Apr 25 '15 at 5:49

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"Justified" in the phrase "justified true belief" means that you have a good reason for your belief. A belief could be justified, yet false, meaning that you have a good reason to believe it, but yet it is not true. (For instance, you could believe it is raining, because it was when you entered the house a few seconds ago, yet it could have stopped in that short of a span of time --your belief is justified but false.)

What counts as a valid justification is controversial.

  • So justified true belief does not equal to knowledge – Sharon Salmon Apr 24 '15 at 18:59
  • 2
    @SharonSalmon Well, it does, in Plato's view, and in the view of many throughout the years. It's still the foundation that most other view of knowledge depart from. My example was meant to show that justification is independent of truth (it is also independent of belief). In Plato's account all three must be present, any two of the three alone are not sufficient. – Chris Sunami Apr 24 '15 at 19:33

Justified true belief has less to do with "Just" in a legal moral since, and more to do with personal beliefs.

  1. Grass is Green
  2. I believe that grass is green.

  3. The Sky is blue

  4. I believe the sky is orange.

We would on a spring day with a healthy lawn say that 2 is a justified true belief.

For 4 we would say my belief was unjustified.

As for the other two questions

What is the act of Justificaton ? What makes something "Just" ?

I'll leave those for someone else to answer, they are pretty loaded questions.

  • What do you mean by "personal beliefs"? – virmaior Jun 21 '15 at 2:53
  • @virmaior The beliefs that an agent has, IE your beliefs that are your personal beliefs. – hellyale Jun 21 '15 at 7:48
  • I take JTB to be a shorthand for the belief knowledge = to be justified in believing something and to so believe it. And those who ascribe to knowledge = JTB generally focus on the conditions of justification. So looking at your 1-4, you could make that clearer by specifying you're asserting 1 and 3 are truth conditions about the world for your thought experiment. 2 and 4 are problematic in that the question is whether knowledge is JTB, and it is certainly true that those are beliefs held by the knower and it is probably true the self has knowledge that it has has such beliefs. – virmaior Jun 21 '15 at 8:02
  • But then what you want 2 and 4 to be is that the fact the knower has belief 2 is knowledge. but that it has belief 4 is not knowledge. But to do that you need to answer at least some conditions for justification. And there, you seem to be asserting that condition of knowledge is that the self believes something true. – virmaior Jun 21 '15 at 8:03
  • @virmaior erm, each one is a stand alone premise. Also you could say Tom believes the sky is orange, instead of "I" en.wikipedia.org/wiki/Belief#Justified_true_belief spells it out better than I do. To say 2 is a justified true belief is to say, why yes, I am right in that belief. To say 4 is not is to say man, how do you justify that belief, look at it, the sky is obviously (in this example) not orange. Premise 2 and 4 are true, in the sense that, I believe those things (In this hypothetical) "The sky is not orange" is a different truth type then "I believe the sky is so" – hellyale Jun 21 '15 at 8:37

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