Jerry R., List:

JR:  "Why even talk about surprise and suspect if instead we can have beans
and bags…or p’s and q’s?"

As I have said over and over, surprise and suspect are the WHY of
reasoning--eliminating the irritation of doubt through the fixation of
belief--while beans and bags or p's and q's serve to illustrate the HOW of
reasoning--forms of inference that produce certain (deduction), probable
(induction), or plausible (abduction) conclusions from true premisses.
This distinction is important to maintain.

JR:  "I may have read wrongly but I recall Ben saying that it *is* a
syllogism and Edwina saying that it *is* modus ponens."

Ben U. quoted Peirce calling hypothesis "minor indirect probable
syllogism."  He later stated, "I'd say that CP 5.189 is a 'syllogism' in a
broad sense admitted by Peirce, though the broad senses are not usual
senses nowadays.  Usually people mean a deductive categorical syllogism, in
Barbara and the rest."  He subsequently added, "I think that the point that
is tripping Jerry R. up is that CP 5.189, as well as modus ponens and
affirming the consequent, are schemata of _*propositional*_ logic, while
the jugglings of Barbara are schemata of *term* logic, and it is terms that
are subject, middle, or predicate."

Edwina just clarified what she said previously--CP 5.189 presents a
deductively INVALID form of modus ponens, which is widely known as the
FALLACY of affirming the consequent.  In her latest example, the conclusion
that it has rained is not certain, as it would be in a deductively valid
argument.  Instead, it is (at best) merely plausible; hence, the argument
is an example of abduction--the proposition that it has rained is a
hypothesis proposed to explain why the car is wet.

JR:  "Besides, affirming the consequent is fine if two things are the same,
isn't it?"

Again, affirming the consequent is a FALLACY in deductive logic.  From "if
p then q" and q, p does not follow necessarily.  I do not know what you
mean here by "if two things are the same."

Regards,

Jon Alan Schmidt - Olathe, Kansas, USA
Professional Engineer, Amateur Philosopher, Lutheran Layman
www.LinkedIn.com/in/JonAlanSchmidt - twitter.com/JonAlanSchmidt
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