A key trade-off in the design of [[knowledge representation]] formalisms is that between expressivity and tractability.[^1] A highly expressive formalism may provide many ways of stating the same fact and create difficulty in querying whereas a highly tractable formalism will invariably oversimplify reality but is easier to use and requires less compute. Another way of describing this is expressive adequacy versus reasoning efficiency or expressiveness versus decidability. [^1]: Levesque, H.J. and Brachman, R.J., 1987. Expressiveness and tractability in knowledge representation and reasoning 1. Computational intelligence, 3(1), pp.78-93.