(EVALUATION OF VALIDITY AND SOUNDNESS. Remember: construct valid arguments. If y

Question

(EVALUATION OF VALIDITY AND SOUNDNESS. Remember: construct valid arguments. If you see that an argument is not valid. Correct it and make a constructive comment.)

Using the following as examples:

Argument 1 is valid. It has the valid form: All A is B; x is A; therefore, x is B. But, it is probably not true that all Democratic leaders want to decrease military spending and increase spending on health care; one counterexample proves this false. What about so-called "blue dog Democrats"? Arguably, President Obama does want to decrease military spending and increase spending on health care; so the conclusion of this argument may be true, and the argument is valid. But one of the premises is false, so it is not sound.

Argument 2 is valid. The argument is a classic modus ponens: If A then B; A; therefore B. The context is unclear here. But, certainly there are many young, beautiful, famous and rich people who are quite unhappy. The major premise is false. Even if it is true that this "friend" is young, beautiful, famous, rich and happy--this argument is unsound.

Argument 3 is valid. This argument is a modus tollens: If A then B; not-B; therefore, not-A. But is it sound? This is the most challenging argument. We do not know the context of the argument. But certainly not all people who identify themselves as Christian are also charitable. One counter-example would prove this premise false. In this particular, artificial case, we do not know this fellow James; the context is unknown. But let's say that it is true that he not charitable, but he identifies himself as a Christian. This argument appears to be valid but unsound. Now, one might dispute this. What if one replied, "all true Christians are charitable". So, even if James claims to be a Christian, if he is not charitable, he is not a Christian. Evaluating this argument will depend on how we define our terms; careful definition, and clarification of terms, are crucial here.

Problem:

Assumption #1

All Middle Easterners can afford and drive Mercedes or expensive cars.

Argument #1

I am Middle Eastern.

Middle Easterners drive Mercedes and expensive cars.

Therefore, I can afford a Mercedes or an expensive car.

Explanation / Answer

Validity:

Assuming that All middle Easterners 'can' afford and drive Mercedes or expensive car ,implies that If I am a middle eastern then certainly I 'can' afford ( and drive as well ) a mercedes or an expensive car. So we see that the argument has been derived form the premises ( it does not matter whether the premises are actually true or not. here actually true means that whether we think it to be true in real world.) So the Argument is clearly VALID.

Soundness:

If we consnider Syria , Iran etc in the Middle East then we find that situation there is bad due to terrorism which leads to poverty . So it can be seen that not everybody can afford expensive cars in the Middle East.(the premises themselves are not true in the real world). Thus the argument is NOT SOUND.

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