Is the Sussman...

...coming up with a new programming language?
http://groups.csail.mit.edu/mac/users/gjs/propagators/
http://www.infoq.com/presentations/We-Really-Dont-Know-How-To-Compute
"I'm at the Strange Loop conference and Gerald Sussman said that all languages are obsolete but called Haskell "the most advanced obsolete language he knows". That's kind of a compliment I guess." - deech

>>18

http://existentialtype.wordpress.com/2011/03/19/dynamic-languages-are-static-languages/

And this is precisely what is wrong with dynamically typed languages: rather than affording the freedom to ignore types, they instead impose the bondage of restricting attention to a single type!

False

Even if in a particular situation we are absolutely certain that a particular value is, say, an integer

Premature optimization

you are depriving yourself of the ability to state and enforce the invariant that the value at a particular program point must be an integer.

That is a trivial invariant. Practical invariants depend upon values and relationships, which cannot be enforced with types unless there are dependant types.

For another, you are imposing a serious bit of run-time overhead

False. Recursive type inference.

Either you give up on modular development, and rely on whole program analysis ...

It's trivial.

or you introduce a static type system precisely for the purpose of recording inter-modular dependencies

Not needed. This can easily be infered by the machine.

The whole-program approach does not scale,

Yes it does.