 Most theorists would say that (1a) is the correct answer to (1), that (1b) is an answer but not the correct answer, and that (1c–e) are not answers to (1) at all. Tichy would say that, among (1a–e), only (1c–d) are answers, and (1c) is the correct answer. Braun (2006) would count (1a–b) as answers and include (1e) as both an answer and a correct answer. What these different theoretical interpretations of the notion of an answer show is there is no univocal pre-theoretical notion of an answer. The notion should rather be seen as a technical one, which can differ from one theory to another. Some theorists make explicit what they understand answers to be, but some leave this implicit. This can be problematic: without explication of which pre-theoretical construct the technical notion of an answer in a given theory is intended to capture, the theory cannot be evaluated empirically.