I am looking for a new philosophical term. A short (perhaps one, two or three syllable) word for an entity that exists but cannot be described completely by any single formal theory (or algorithm). I believe human beings, their societies and cultures are such entities, but I think many physical systems are such entities as well. The word “system” actually does not fit here because it has a connotation of something systematic, that is something that can be captured completely by some theory. I am thinking of physical entities for which the set of equations describing them cannot be solved except for special cases, i.e. where the mathematical description contains functions that are not turing-computable. In mathematics, such entities are known, entities for which it can be shown that every formal theory of them is incomplete. You may always be able to extend a given theory, but the resulting theory will be incomplete again. Such entities cannot be exhaustively described in terms of a formal theory. If physical “systems” of this kind exist, they cannot be perfectly simulated by any algorithm. They would generate new information (new with respect to any given theory). Something as simple as a set of three bodies moving around each other might already be such a system (it looks like the “three body problem” cannot be solved exactly. Kurt Ammon called (a certain kind of) such objects “creative systems” but I want to avoid the term “system”. Any suggestions? It might be a synthetic neologism, but should capture the idea in such a way that it has a chance to catch on.

Much of science is built on the tacit assumption that everything can be described in terms of formal theories. Everything is a “system” in this sense. But this is just a hypothesis and I think it is wrong. In mathematics, there are mathematical entities that are not completely formalizable (i.e. they have more true properties than can be derived in any single theory about them). If such things exists in mathematics, there is no a-priori reason they cannot exist in physical reality as well. What exists and what can be formalized is not necissarily the same. I want a short and crisp term for the unformalizable. The hypothesis that everything that exists is formalizable is built into our language. There is no short, simple word for the non-formalizable (yet). There is a large range of possibilites we cannot see because our language has been restricted.