What is Expressiveness in a Computer Language

[Marshall]

Chris F Clark wrote:
>
> I'm particularly interested if something unsound (and perhaps
> ambiguous) could be called a type system.  I definitely consider such
> things type systems.

I don't understand. You are saying you prefer to investigate the
unsound over the sound?


> However, I like my definitions very general and
> vague.  Your writing suggests the opposite preference.

Again, I cannot understand this. In a technical realm, vagueness
is the opposite of understanding. To me, it sounds like you are
saying that you prefer not to understand the field you work in.


> To me if
> something works in an analogous way to how a known type system, I tend
> to consider it a "type system".  That probably isn't going to be at
> all satisfactory to someone wanting a more rigorous definition.

Analogies are one thing; definitions are another.


> Of
> course, to my mind, the rigorous definitions are just an attempt to
> capture something that is already known informally and put it on a
> more rational foundation.

If something is informal and non-rational, it cannot be said to
be "known." At best, it could be called "suspected." Even if you
think something which turns out to be true, we could not say
that you "knew" it unless your reasons for your thoughts were
valid.

I flipped a coin to see who would win the election; it came
up "Bush". Therefore I *knew* who was going to win the
election before it happened. See the probem?


Marshall