I'm a mathematician, and sometimes I need to assess the level at which I'll pitch an explanation. Although I don't do this in a setting where it's possible to set a test, as such, I do ask this question: An equivalence relation is reflexive, symmetric, and transitive. If E is an equivalence relation, and we know E(x,y) but we know !E(y,z), what do we know about E(x,z), and why? It seems a great filter for people who…
E(x,y) & E(y,z) => E(x,z)
but since we know !E(y,z), we can infer !E(x,z).(I'm not a logician, either, so I hope you'll excuse what may be imprecise phrasing on my part.)