Abstract

Nozick is the author of the conditional definition of knowledge where two subjunctive conditionals replace internalistic notion of justification. If you know that p, you have true belief that p and also in the close possible worlds you would accept p when p is true and you would not accept p when p is false. Nozick agrees with skeptics that we do not know that we are not brains in the vat. But he claims that we do know all the trivial things we think we know. The only way to accept the two theses is to deny the Principle of Clousure. According to Nozick knowledge is not closed under known logical implication. But is it right to deny the principle? Our everyday knowledge implies that the skeptic is wrong. If I know that I am reading a text on Earth, it is false that I am on Alpha Centauri floating in a tank. To reject skeptic it is enough to deny the transparency principle (if I know, I know that I know). When knowledge is possible without knowledge about that knowledge, we can know even if we are not able to prove that we know