There's been a lot of discussion on here about who is, or is not, a musician; but in fact, a musician is not even a musician!

Here’s my proof.

Let us take an accomplished singer, A, who can play no musical instrument other than her voice.

By any reasonable definition, the human voice is a musical instrument. And a musician is someone who plays a musical instrument.

Therefore, A = musician.

Now let us take an accomplished harp player, B.

Is B also a musician? Yes, from the definition of ‘musician’.

And is B an instrumentalist? Yes again, as the word signifies playing an ‘external’ musical instrument.

Therefore, B = instrumentalist = musician.

But is A an instrumentalist? No; as already stated, being an instrumentalist signifies playing an external musical instrument, such as the harp; and A can play no instrument other than her voice.

Therefore, A = non-instrumentalist.

But instrumentalist = musician, therefore non-instrumentalist = non-musician.

A = musician, but also, A = non-instrumentalist = non-musician.

Therefore, musician = non-musician.