A pure forward chaining implementation of the RDFS closure rules
based upon the basic forward rule interpreter. The normal mixed
forward/backward implementation is generally preferred but this has
two possible uses. First, it is a test and demonstration of the forward
chainer. Second, if you want all the RDFS entailments for an entire
dataset the forward chainer will be more efficient.
author: Dave Reynolds version: $Revision: 1.9 $ on $Date: 2008/01/02 12:07:47 $