 Now that we have separated types of ambiguity, we may reasonably ask how we tell when a term or phrase contains an ambiguity. The answer may be disappointing – there are tests and considerations but no firm answers and probably a lot depends on what the ‘best theories’ in linguistics etc. end up looking like. Nevertheless, we can make some progress. The canonical source for these tests is Zwicky and Sadock’s ‘Ambiguity Tests and How to Fail Them’ (1975).