The quote I learned about the Great Vowel Shift from was Henry IV, Part I. If reasons were as plentiful as blackberries, where the prof explained it was a pun

The quote I learned about the Great Vowel Shift from was Henry IV, Part I. If reasons were as plentiful as blackberries, where the prof explained it was a pun because "reasons" was pronounced more like "raisins" in 1597.