On Mon, 7 Nov 2016 17:15:44 -0800
Jeffrey Brown <[log in to unmask]> wrote:

> I am confused about how to distinguish clitics from affixes. This
> does not seem to me to be a clearcut distinction. Can anyone give me
> a definitive guideline?

An affix is generally inseparable from a root or stem.
A clitic has a fixed position relative to some sentence element.
A word is free.

Obviously these are really three points on a continuum, and there are
going to be marginal cases.

Affixes can't normally be split off, but a recorded Italian sentence is
E proprio -accio? "Is it really bad?"
like something out of Esperanto.

Similarly, Bloomfield defined a word as the minimal free unit:
What colour was it? — Red.
but it's hard to find a use of "and" as a sentence.

In the French "je ne le vois pas", the order is absolutely fixed and
you can't insert anything between the components, which encourages one
to say everything bar "vois" is a clitic. Certainly you can't have "je"
as a sentence.

You might say a clitic is something that lies on the borderline between
being a word and being an affix.