I totally agree 🙂

If it turns out that I don’t have hands – perhaps they are an illusion created by an evil demon – then my belief was false and the evidence that I had hands was insufficient to justify my belief.

It it were later to be shown that you don’t have hands, was the original knowledge show to be false, unjustified, or both.

All the evidence supports my belief that I have hands. The Matrix hypothesis and the Evil Demon hypothesis are not plausible. My belief is justified beyond a reasonable doubt. I know I have hands.

Would you say you know you have hands?

I agree with everything you say, but the element the court got wrong in the first instance was the T part of JTB. They had false knowledge or thought they knew but in fact didn’t.

Now, on the question of is knowledge provisional, then yes I think so. We should always be willing to accept new evidence that challenges our beliefs, but we must act and change our beliefs if we are warranted in doing so. But if we are shown to be wrong then it isn’t necessarily the justification that was the error (it might be if we had no good reason for the belief) it can also be the truth and the falsity of the knowledge does not automatically mean it was poor justification.

I think my little dog has no words but I think she is conscious of the universe.

I am 100% sure that I think therefore I am. I am not so sure that I have hands though because an evil demon (or The Matrix) might be fooling me.

I believe beyond a reasonable doubt that I have hands. I know it provisionally but I’ll update my belief if new evidence comes to light.

I am 100% sure that, in Euclidian geometry, the angles of a triangle sum to 180°. I am sure of this because Euclid designed the system so that it is inevitably true. But synthetic facts are not inevitably true in the real world. We should hold them lightly and be open to new information. On the surface of the earth, angles in triangles do not sum to 180° because, it turns out, the earth is not flat.

The True part did not change during the retrial. A either did the crime or they did not. This is true during both the original trial and the retrial. The J relates to how much evidence you have.

C1 was provisionally sound but the second part of the argument takes place at a later time. At the time of the second part of the argument (the retrial), your new evidence shows that P1 is not (and was not) true. You thought the conviction was justified but you were mistaken. There is no contradiction.

Criminal Law has a mechanism for revisiting bad reasoning or for correcting invalid premises. All convictions are provisional and can be corrected if new evidence comes to light. The same is true in science. If your geocentric model of the solar system disagrees with the data, the model is incorrect and you need a new model.

The same should be true in philosophy. Knowledge is provisional.