Now let's ask Cassie questions about what we've told her. One way
to do this is by asking SNePS to find nodes. To do this,
we need to describe the node(s) we want SNePS to find. Like assert, the SNePSUL command find can take relation-node pairs
as arguments.
E.g., suppose we ask Cassie who is an elephant. One way to ask
this is to ask SNePS to find all propositions that say who is an
elephant. To do this, we want to find all nodes that have
a class arc coming out of them and pointing to the elephant node, since that uniquely describes all propositional
nodes that represent that something is an elephant. (See
UM§2.11.)
