No subjects. An entry is not filed under anything — no classes, no top-level categories, no taxonomy.
The borders between disciplines are not in the world. They sit in the organisation of universities, journals and funding: vocabularies built around durable institutional purposes, kept because institutions need them, not because the world divides there.
What forces it
Ask an intelligence a question today and the answer moves from biomineralisation to crystallography to semiconductor fabrication without crossing a border, because there is no border to cross. Knowledge produced this way arrives unsorted. Filing it into disciplines afterwards is a distortion introduced at the moment of storage, not a property of the material.