Expert systems didn't use neural nets or in fact any machine learning. They did interviews with experts and tried to do domain modeling, mapping the expertise

Expert systems didn't use neural nets or in fact any machine learning. They did interviews with experts and tried to do domain modeling, mapping the expertise to a formal symbolic logical description, ontologies, relations etc. Both the knowledge base and the inference engine changed. They both changed to a unified machine learning paradigm. It's like you throw away your axe's handle, then the head, and then you grab a chainsaw. It's "the same thing" to that same degree.