Opinion polls taken just before the1980 election showed the Republican Ronald Reagan decisively ahead of the Democrat Jimmy Carter, with the other Republican in the race, John Anderson, a distant third. Those apprised of the poll results believed, with good reason:
[1] If a Republican wins the election, then if it's not Reagan who wins it will be Anderson.
[2] A Republican will win the election. Yet they did not have reason to believe
[3] If it's not Reagan who wins, it will be Anderson
How? — Banno
[1] If a Republican wins the election, then if it's not Reagan who wins it will be Anderson.
Yet — Banno
Sure.
But (1) is true. — Banno
It's just a case of the so called “paradoxes of material implication”. — Amalac
[1] If a Republican wins the election, then if it's not Reagan who wins it will be Anderson.
[2]A Republican will win the election.
If it's not Reagan who wins, it will be Anderson
then if it's not Reagan who wins it will be Anderson.
Keep track of domains. — fdrake
The propositions don't involve quantifiers. There's no issue of domains. — TonesInDeepFreeze
Premise 2 is false — Amalac
At a point before the election, with 'win's understood as 'will win', then R v A is true.
At a point after the election, with 'wins' understood as 'won', then R v A is true. — TonesInDeepFreeze
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