Sentence:  It may be assumed as a starting-point, that the case-affixes are remnants of nouns or perhaps pronouns, which have been cut down and worn away by use. I think it will be admitted by all philologists that any other assumption would be irreconcileable, not only with the fundamental principles of modern Aryan <WSD>glossology</WSD>, but with the universal laws of language. 
Meaning of the word marked with <WSD> tags:  The science of language; linguistics.