Information Technology Reference
In-Depth Information
4.2.4.1
Abduction
In its most general form, abduction is the process behind insight. It is involved in
three classes of activity:
•
Retroduction
:
Open retroduction
is the
creation
of a new hypothesis and
closed
retroduction
is the
selection
of a hypothesis from a pre-defined set. Often only
closed retroduction is referred to as 'abduction' in the literature, and this limited
view depends upon the notion of
reverse implication
. Thus, if (A implies B) then
we can say that if we observe B then A is a possible cause. However, this inference
is closed because it depends upon the pre-existence of propositions such as (A
implies B). Such a predefined system is closed.
•
Abstraction
:
Open abstraction
is the process of creating or observing new tax-
onomic concepts and
closed abstraction
is the process of selecting taxonomic
concepts from a pre-defined set.
•
Heuristic
:
Heuristic abduction
is the insight that creates or selects the process
(the heuristic) of how to solve a problem. The heuristic tells the inference process
how to continue with deduction. Whereas heuristic knowledge, as defined earlier,
selects a path of reasoning, the heuristic abductive inference proposes how such
a decision should be made.
4.2.4.2
Induction
Open induction
, taken in the context of the other forms of inference defined here,
is the
process of validating a hypothesis
. Validation involves induction that is not
enumerative, that is, does not involve generalising from a set of particulars, as it
is normally understood.
Induction
here requires the pre-existence of a hypothesis,
a deductive procedure and a set of criteria. The categories of criteria are shown in
Fig.
4.1
.
The normal definition of induction,
and one not fully supported here, is based upon
the principle of generalisation from a given set of instances. In practice this view
combines the notions of validation with retroduction
(Strawson
1952
). 'Induction'
in this combined sense is the process of reasoning where the conclusions are not
entailed by the premise (i.e. truth is not guaranteed to be preserved). Thus statements
like:
He's been travelling for 24 hours, so he'll be very tired
can be explained by a suppressed premises (undeclared hypotheses) such as:
People who travel for 24 hours will be very tired
Such suppressed premises allow us to reconstruct the 'inductive' inference
as a
form of deductive inference
. However, the suppressed premises do not appear as
conclusions to deductive arguments based on particular instances (examples drawn
from the extensions of the premises). 'Induction', as held by this common view,
