# If (A+B) then C

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3. » If (A+B) then C

Tue 16 Jun, 2009 11:36 am
I am confused a few answers in this truth table:

http://www.philosophyforum.com/forum/philosophy-forums/branches-philosophy/logic/4698-argument-tautologically-valid.html

We have the (A+B) then C

A/B

F/T then F
T/F then F
F/F then F

Supposedly the first of these is False, and the next two are true and I can't figure out why. I would assume the person is mistaken.

My reasoning is that the fact that A+B are bracketed would make (A+B) False in each example, which would leave us with

F then F
F then F
F then F

Which in my mind, in the construction of a truth table would make each True, and not simply the latter two. Some help??? I would be grateful.

Horace phil

Tue 16 Jun, 2009 01:48 pm
@Horace phil,
I am concerned about line 6,7,8, 14,15, 16 but only the values found under the first therefore sign. To my mind each should be true...

1. Philosophy Forum
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3. » If (A+B) then C