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Identifying/ Reconstructing Arguments

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1 Identifying/ Reconstructing Arguments

2 First, is there an argument?
Is the author trying to convince me/provide evidence? to explain? to inform? to entertain? etc. Argument consists of premises, conclusion, where premises are offered as evidence for conclusion. Often the premises are given first, but not always.

3 Principle of charity Interpret your author in the most charitable way that is reasonably possible as making the best argument possible. as endorsing mostly true or plausible premises. as offering mostly valid or inductively strong arguments.

4 Straw-man fallacy Offering an uncharitably weak reconstruction of your opponent’s argument, before attacking it Setting up a “straw man” then knocking it down

5 Indicator terms “thus”, “therefore”, “hence”, “since”, “because”, “so”, etc. But these have other uses, besides indicating that a conclusion is being drawn. “Since” is sometimes temporal, explanatory. “Because” is sometimes explanatory.

6 Evidence or explanation?
The NCAA will soon change the eligibility rules because of the public demand The NCAA will soon change the eligibility rules because of the public demand. Enthymemes, again Evidence or explanation? Background knowledge, not just of NCAA, but of conversational context Is it known/agreed that NCAA will change rules? The public demand is ... high? very high? low? The NCAA will soon change the eligibility rules

7 An Extended (and Difficult) Example

8 Aquinas on the existence of God
The second proof is from the nature of the efficient cause. We find in our experience that there is a chain of causes. It is not possible for anything to be the efficient cause of itself, since it would have to exist before itself, which is impossible. Nor in the case of efficient causes can the chain go back indefinitely, because in all chains of efficient causes, the first is the cause of the middle, and these of the last, whether they be one or many. If the cause is removed, the effect is removed. Hence, if there is not a first cause, there will not be a last, nor a middle. But if the chain were to go back infinitely, there would be no first cause, and thus no ultimate effect, nor middle causes, which is admittedly false. Hence we must presuppose some first efficient cause—which all call God.

9 First, identify the main conclusion.

10 Aquinas on the existence of God
The second proof is from the nature of the efficient cause. We find in our experience that there is a chain of causes. It is not possible for anything to be the efficient cause of itself, since it would have to exist before itself, which is impossible. Nor in the case of efficient causes can the chain go back indefinitely, because in all chains of efficient causes, the first is the cause of the middle, and these of the last, whether they be one or many. If the cause is removed, the effect is removed. Hence if there is not a first cause, there will not be a last, nor a middle. But if the chain were to go back infinitely, there would be no first cause, and thus no ultimate effect, nor middle causes, which is admittedly false. Hence we must presuppose some first efficient cause—which all call God.

11 Aquinas on the existence of God
The second proof is from the nature of the efficient cause. We find in our experience that there is a chain of causes. It is not possible for anything to be the efficient cause of itself, since it would have to exist before itself, which is impossible. Nor in the case of efficient causes can the chain go back indefinitely, because in all chains of efficient causes, the first is the cause of the middle, and these of the last, whether they be one or many. If the cause is removed, the effect is removed. Hence if there is not a first cause, there will not be a last, nor a middle. But if the chain were to go back infinitely, there would be no first cause, and thus no ultimate effect, nor middle causes, which is admittedly false. Hence we must presuppose some first efficient cause—which all call God—exists… main conclusion

12 Then, identify the main argument.
Use indicator terms if they’re helpful.

13 Aquinas on the existence of God
The second proof is from the nature of the efficient cause. We find in our experience that there is a chain of causes. It is not possible for anything to be the efficient cause of itself, since it would have to exist before itself, which is impossible. Nor in the case of efficient causes can the chain go back indefinitely, because in all chains of efficient causes, the first is the cause of the middle, and these of the last, whether they be one or many. If the cause is removed, the effect is removed. Hence if there is not a first cause, there will not be a last, nor a middle. But if the chain were to go back infinitely, there would be no first cause, and thus no ultimate effect, nor middle causes, which is admittedly false. Hence we must presuppose some first efficient cause—which all call God—exists.

14 Aquinas on the existence of God
The second proof is from the nature of the efficient cause. We find in our experience that there is a chain of causes. It is not possible for anything to be the efficient cause of itself, since it would have to exist before itself, which is impossible. Nor in the case of efficient causes can the chain go back indefinitely, because in all chains of efficient causes, the first is the cause of the middle, and these of the last, whether they be one or many. If the cause is removed, the effect is removed. Hence if there is not a first cause, there will not be a last, nor a middle. But if the chain were to go back infinitely, there would be no first cause, and thus no ultimate effect, nor middle causes, which is admittedly false. Hence we must presuppose some first efficient cause—which all call God---exists..

15 Aquinas on the existence of God
The second proof is from the nature of the efficient cause. We find in our experience that there is a chain of causes. It is not possible for anything to be the efficient cause of itself, since it would have to exist before itself, which is impossible. Nor in the case of efficient causes can the chain go back indefinitely, because in all chains of efficient causes, the first is the cause of the middle, and these of the last, whether they be one or many. If the cause is removed, the effect is removed. Hence if there is not a first cause, there will not be a last, nor a middle. But if the chain were to go back infinitely, there would be no first cause, and thus no ultimate effect, nor middle causes, which is admittedly false. Hence we must presuppose some first efficient cause—which all call God—exists..

16 Aquinas on the existence of God
The second proof is from the nature of the efficient cause. We find in our experience that there is a chain of causes. It is not possible for anything to be the efficient cause of itself, since it would have to exist before itself, which is impossible. Nor in the case of efficient causes can the chain go back indefinitely, because in all chains of efficient causes, the first is the cause of the middle, and these of the last, whether they be one or many. If the cause is removed, the effect is removed. Hence if there is not a first cause, there will not be a last, nor a middle. But if the chain were to go back infinitely, there would be no first cause, and thus no ultimate effect, nor middle causes, which is admittedly false. Hence we must presuppose some first efficient cause—which all call God—exists.. { } { }

17 Disjunctive syllogism
God exists. There is a first cause. Disjunctive syllogism Nothing causes itself. Either there’s a first cause, or the chain of causes goes back infinitely, or something in the chain caused itself. The chain doesn’t go back infinitely.

18 Work out the subsidiary arguments.

19 Aquinas on the existence of God
The second proof is from the nature of the efficient cause. We find in our experience that there is a chain of causes. It is not possible for anything to be the efficient cause of itself, since it would have to exist before itself, which is impossible. Nor in the case of efficient causes can the chain go back indefinitely, because in all chains of efficient causes, the first is the cause of the middle, and these of the last, whether they be one or many. If the cause is removed, the effect is removed. Hence if there is not a first cause, there will not be a last, nor a middle. But if the chain were to go back infinitely, there would be no first cause, and thus no ultimate effect, nor middle causes, which is admittedly false. Hence we must presuppose some first efficient cause—which all call God—exists…. ( )( { ) } { }

20 Disjunctive syllogism
God exists. There is a first cause. Disjunctive syllogism Nothing causes itself. Either there’s a first cause, or the chain of causes goes back infinitely, or something in the chain caused itself. The chain doesn’t go back infinitely. To cause itself, something would have to exist before itself. Nothing exists before itself.

21 Aquinas on the existence of God
The second proof is from the nature of the efficient cause. We find in our experience that there is a chain of causes. It is not possible for anything to be the efficient cause of itself, since it would have to exist before itself, which is impossible. Nor in the case of efficient causes can the chain go back indefinitely, because in all chains of efficient causes, the first is the cause of the middle, and these of the last, whether they be one or many. If the cause is removed, the effect is removed. Hence if there is not a first cause, there will not be a last, nor a middle. But if the chain were to go back infinitely, there would be no first cause, and thus no ultimate effect, nor middle causes, which is admittedly false. Hence we must presuppose some first efficient cause—which all call God—exists…. { } ( { ) }

22 These are the unargued premises.
God exists. There is a first cause. Disjunctive syllogism Nothing causes itself. Either there’s a first cause, or the chain of causes goes back infinitely, or something in the chain caused itself. The chain doesn’t go back infinitely. Modus tollens To cause itself, something would have to exist before itself. Nothing exists before itself. If the chain is infinite, there are no causes now. There are causes now. Hypothetical syllogism If the chain is infinite, there’s no first cause. If there’s no first cause, there are no causes now These are the unargued premises. If the cause is removed, the effect is removed.


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