The present work is a continuation of the authors' acclaimed multi-volume A
Practical Logic of Cognitive Systems. After having investigated the notion of
relevance in their previous volume, Gabbay and Woods now turn to abduction. In
this highly original approach, abduction is construed as ignorance-preserving
inference, in which conjecture plays a pivotal role. Abduction is a response to
a
cognitive target that cannot be hit on the basis of what the agent currently
knows.
The abducer selects a hypothesis which were it true would enable the reasoner to
attain his target. He concludes from this fact that the hypothesis may be
conjectured. In allowing conjecture to stand in for