Turing Machines and Conenctionist networks

[Jim Hendler]

For what it is worth, I've just been having a chat
with my friend down the hall,  a learning theorist.
We've sketched out a proof that shows that non-recurrent
back-propagation learning cannot be Turing equivalent (we
can show a class of Turing computable functions which such
a machine could not learn - this is even assuming perfect 
generalization from the training set to an infinite
function).  Recurrent BP might or might not,
depending on details of  the learning algorithms which we'll
have to think about.
 cheers
 Jim H.