I like the James Nicholl quote; there's a lot of truth in it. However, it is also true to say that English (whatever that might originally have been) has suffered invasions from other languages, to which purists (whatever they might be) tend to object.

Every language starts somewhere, and develops from something. The concept of purity of a language is not easy to define. As far as making rules is concerned, I defy anyone to make a clear rule for constructing plurals in Welsh.

There never was nothing.