On Fri, 15 Oct 2010 02:30:37 +0100, And Rosta <[log in to unmask]> wrote:

>It's never been clear to me why an engelang should have any kind of regular
derivational morphology. (That is, what sort of engelang design goals would
be satisfied thereby?) I can certainly see how it can be desirable for words
with similar meaning to have some similarity of form, but I can't see why
that needs to be done by regular derivational morphology, and indeed, given
that derivational morphology is essentially semantically irregular (else
it's just a kind of syntax), there's a case for saying it should be
irregular at the level of form too.

Yeah, I've wondered a similar wonder.  The idea that one ought to have a
_word_ for any of various meanings X seems to hold sway over people in a way
that having a fixed multi-word compositional expression for X has trouble
displacing where it arguably ought.  

Sai points out that compactness is a frequent engelanger's desideratum and
can be a genuine reason to use regular derivational morphology instead of
syntax.  This is especially so in the presence of phonotactic constraints
imposing a minimum word length larger than the minimum affix length.  (It's
hard to beat, e.g., mutations and morphological tone for compactness.)