# valid statement or not?

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• Jun 24th 2007, 01:22 PM
Ilaggoodly
if all else fails, you can prove its wrong by giving an example of a situation in which it would be wrong, i.e. constructing a truth table.
• Jun 24th 2007, 01:32 PM
Soroban
Hello, TheRekz!

Quote:

Quincy likes all action movies.
Quincy likes the movie "Eight Men Out".
Therefore, "Eight Men Out" is an action movie.

You must learn to break down the argument into single statements.

Let $p$: It is an action movie.
Let $q$: Quicy likes the movie.

We are told: "Quincy likes all action movies."
This means: "If it is an action movie, then Quincy likes the movie".
. . Symbolically: . $p \rightarrow q$

We are told that: "Quincy likes the movie", $q$

The conclusion is: "Therefore, the movie is an action movie, $p$.

The argument has the form: . $\begin{array}{c}p \rightarrow q\\ q \\ ---- \\ \therefore\;p\end{array}$

This is not valid . . . fallacy of the converse.

• Jun 24th 2007, 02:13 PM
Plato
Quote:

Originally Posted by Soroban
The argument has the form: . $\begin{array}{c}p \rightarrow q\\ q \\ ---- \\ \therefore\;p\end{array}$

This is not valid . . . fallacy of the converse.

This fallacy is also known as Affirming the consequent.
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