|Imperatives: Commands are similar to statements, but do not establish any facts. The question is whether truth values can be attributed to them in logic, e.g. if they are obeyed or not obeyed. With a rewording like "It is necessary that ..." commands can be aligned to factual findings.|
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Command/Moral/Logic/Geach: a statement-line cannot be in an if-clause. - "If you want ..." these are real imperatives, only grammatically a hypothetical sentence. - The wish itself has nothing to do with the truth conditions. - But an utterance does not get empty qua imperative, simply because it cannot be fulfilled.
Imperative/Logic/Geach: difficult problems: "Tu x or tu y!" Cannot be interpreted as "I command x or I command y" - analog to assertions: l- p v q cannot be interpreted as l-p or l-q.
Solution/Hare/Geach: distinction neustic/tropic/Hare (> Hare, R.M.) - E.g. tropic: is identical in "Tu x or tu y" and "You will do x or you will do y". - Phrasticon: "Your future doing of either x or y" - Neusticon: "Please!" or yes". (assertorically).
Disjunction/Geeach: it belongs to the tropic. - Neustic: is added to the tropic as a whole, not to one or the other disjoint.
Zoglauer I 23
Definition Tropic/Hare: descriptive component of a standard sentence-
Definition Neustic/Hare: prescriptive component of a standard sentence.
Logic Matters Oxford 1972
Einführung in die formale Logik für Philosophen Göttingen 2002