There are formations in Greek and Latin and English which have hitherto baffled all tests; and there are certain contrivances, such as the augment in Greek, the change of vowels in Hebrew, the Umlaut and ablaut in the Teutonic dialects, where we might feel inclined to suppose that language admitted distinctions purely musical or phonetic, corresponding to very palpable and material distinctions of thought.
"Lectures on The Science of Language"
Max Müller