Statement: "Absolute certainty cannot be achieved."
That statement clearly disproves itself. If instead it would read "Based on much experience, I believe strongly that absolute certainty cannot be achieved", it would not be a paradox.
With the statement, the speaker claims to know something about all existing and possible consciousnesses (inside or not inside of the system of the universe), how they experience and interpret reality (if they have any reality except for their own mind) and how they reason. It is a statement that implies that the person stating it knows consciousness in an abstract way.
Let's think:
Do I *know with absolute certainty* that absolute certainty cannot be achieved? No, I obviously can't know that with absolute certainty (because if the statement were true, then it were impossible to know with absolute certainty *that* it is true).
And if the statement were not true, I could obviously also not know with absolute certainty that the statement were true because it weren't.
Actually, we just found out that the statement *is wrong*! Meaning: Absolute certainty can be achieved. How so? Read this statement: "If absolute certainty cannot be achieved, then I cannot know with absolute certainty that this is so." The statement uses logic. And the logical conclusion is absolute, its truth cannot be denied. So we now know something with absolute certainty. Hence the statement that absolute certainty cannot be achieved has been demonstrated to be incorrect.
I think we just made the step from faith to knowledge. Might take a few weeks to sink in.
sincerely yours
dad