Here is a massive philosophy joke from my country. If you don't know
Jára Cimrman, then in short: he's a fictional Czech genius that the country pretends has actually existed and basically invented everything that's credited to other geniuses and was completely forgotten by history. The character was created by a bunch of amateur actors who made a lot of plays about him which got immensely popular and are now part of Czech culture. Each play is traditionally preceded by a lecture where the Cimrman "historians" present various findings about him -- it turns out he was the world's best inventor, engineer, poet, educator and, of course, philosopher too. In one lecture they present his philosophical theory of knowledge. Below is a video, in Czech -- there is some weird thing going on with subtitles, I can turn on auto-translated English subtitles in Freetube but for some reason English is missing in the embedded YouTube player here, so I'll also add an auto translate of the original text below (it may actually be even better than the subtitles as there's no speech recognition going on).
Only recently did I discover a letter in Einstein's correspondence in which Cimrman introduces his friend to the definitive outline of externalism. He explains to him that according to this philosophy, the existence of things is exactly the opposite of what is commonly believed: a thing is where we think it is not, and is not where we think it is. In other words, in popular terms: if I hold this piece of chalk in my hand, for example, then according to Cimrman, this chalk fills the entire space around it continuously, and only in the place you see is this chalk not there. What I hold in my hand is actually just a kind of empty bubble in a continuous mass of chalk. Einstein found such a description of the world remarkable. - In the original, he even called Cimrman's views "funny". - However, he also had objections. I quote: "As a physicist, I must point out to you that nothing changes about the essence of reality itself if you label a THING as VOID and an empty environment as a THING. That is just a play on words." In the original: "The ping-pong with the words." - So much for Einstein.
(youtube video starts here)
Before I introduce you to Cimrman's answer to this objection of Einstein's, I must mention the philosopher F. C. Bohlen, whose name probably means nothing to you today. No wonder: he was active in philosophy only as a dilettante. His own profession was a merchant - he had a large drugstore in Essen. And he was perhaps only famous for being rude and vulgar to his customers. Well - and this vulgar materialist also got involved in philosophy. And it is precisely in comparison with his theory of knowledge that Cimrman explains his own principles of knowledge to Einstein. I will quote them according to Cimrman's letter.
According to the vulgar materialist Bohlen, the basic concept of our knowledge is TRUTH, even though Bohlen admits that it is initially INACCURATE. Cimrman, on the other hand, says that the basic concept of knowledge is ERROR, initially of course ACCURATE.
As our knowledge deepens, we reach the second phase of the cognitive process, in which, according to Bohlen, WE REFINE THE TRUTH, while according to Cimrman we only REFUTE THE ERROR.
The ultimate goal of our knowledge, according to Bohlen, is then the state when the truth is already absolutely accurate and we WE KNOW EVERYTHING. According to Cimrman, at the end of the cognitive process, error is completely refuted and we KNOW NOTHING.
But be careful. I would not like you to consider Cimrman to be some kind of agnostic or nihilist. He understands knowledge as an essentially positive process, in which we free ourselves from the initial error, so that - as he literally says - "we finally stand before the face of the Universe with a clear and empty head." The fact that we know nothing at the end of knowledge is only a logical consequence of his externalism. In the process of knowledge, as we have shown in this chalk, we approach the place where the thing is not. If we therefore reach the object itself, we do not reach, as Bohlen claims, the core of the thing, but we step into the void. So at the end of the cognitive process we do not know anything, but we know it correctly.
But here again the proverbial Cimrman contradiction (Cimrmanscher Widerspurch) occurs: his theory of knowledge can be applied to the whole of existence, but with one exception - and that is Cimrman's theory of knowledge itself. Applied to itself, it refutes itself: either it is ERROR, or we DO NOT KNOW it.
However, Cimrman knew his way around here too. Just before he uttered his final sentence WE KNOW NOTHING, he took a so-called STEP SIDEWAYS. This put him - but only for a moment - on the ground of vulgar materialism, from where he could acknowledge his theory of knowledge as objectively true and then return back.
Cimrman then connected the conclusions of both theories with the so-called COLON OPERATOR, which gives both contradictory statements a common outcome in the famous philosophical sentence: WE KNOW EVERYTHING: WE KNOW NOTHING.