Arguments, Premises and Conclusion

1. Arguments, Premises and Conclusion Fundamentals of Logic Unit – 1 Chapter – 2

2. The relationship among argument, premises and conclusion:

3. Arguments: • Argument is a statement or set of statements that you use in order to try to convince people that your opinion about something is correct. • With propositions as building blocks, we construct arguments. • In any argument, we claim one proposition on the basis of some other propositions. • While doing this, we come to draw inferences.

4. Inferences: • Inference is a process that may tie together a cluster of propositions. • In which some inferences are correct and other are not. • Such cluster of propositions constitutes an argument. • Therefore it is the duty of a logician to analyze these cluster, examine the propositions and the relations among these propositions.

5. Argument: • Argument is a technical term in logic. • It need not to involve disagreement or controversy. • In logic, argument refers • to any group of propositions of which one is claimed to follow from other, which are regarded as providing support for the truth of that one. • A mere collection of propositions can not be an argument as we can find in writing or in speech.

6. Contd… • Rather there must be the internal structure ( inference) that leads to a conclusion. • In other words, we can describe this structure with the terms, premises and conclusion.

7. Premises and Conclusion: • Premises are the cluster of propositions that are interlinked to each other that provide support for the conclusion. • Conclusion of an argument is the proposition that is affirmed on the basis of the other propositions of the argument e.g. • Most actors are celebrities. (premise) • Rajesh Hamal is an actor. (Premise) • Therefore Rajesh Hamal is probably a celebrity. (conclusion)

8. Contd… • If I owned all the currency in the Rastra bank of Nepal, then I would be wealthy. (premise) • I do not own all the currency in the Rastra Bank. (premise) • Therefore I am not wealthy. (conclusion) • Arguments are found in different areas such as in politics, ethics, sports, religion, science, law and in everyday life.

9. Contd… • Those who defend these arguments or who attack them, are usually aiming to establish the truth (or falsify) of the conclusions drawn. • As logicians, our concern here are chiefly two: • First concern is about the form of an argument, to determine whether the argument of this kind is likely to bring a correct conclusion or not. • Second concern is about the quality of the argument, to determine whether it in fact gives a correct conclusion or not.

10. Arguments: • Arguments vary greatly in the degree of their complexity. • Some are very simple but other are quite intricate: • sometimes because of the structure or formulation of the propositions they contain and • Sometimes because of the relations among the premises and • Sometimes because of the relations between premises and conclusion.

11. Types of Arguments:

12. Simple Arguments: • Simple kind of arguments are short and simple that consists one premise and one conclusion that is claimed to follow from it. • Each may be stated in the separate sentence e.g. • No one was present when life first appeared on the earth. Therefore any statement about life’s origins should be considered as theory, not fact.

13. Simple Argument: • Sometimes both premise and conclusion may be stated within the same sentence e.g. • Since it turns out that all humans are descended from a small number of African ancestors in our recent evolutionary past, believing in profound differences between the races is as ridiculous as believing in a flat earth.

14. Complex Arguments: • Complex types of arguments are those in which there are more than one or many premises that follow the conclusion. • In such arguments, conclusion may occur at any place like in the following examples: A. An absolute certainty in the women’s race is that the record will not be broken. (1) The market has been formed using 2: 15.25 as the benchmark; a time set by Radcliffe in 2003 using male pacemakers. (2) London subsequently decided to stage the race under championship conditions which does not allow for pacemakers. (3) And anyhow, none of this year’s competitors have yet run sub-2:20, so it will be miracle if they get within four minutes of it.

15. Contd… • This is the example of an argument whose three premises appear after the conclusion is stated. B. (1) SanathJayasuria yesterday … was unlucky to … end an innings of monumental endurance of 340 played mostly in torrid heat and energy sapping conditions…. (2) Roshan … with his double century… too was very correct in his stroke play and the world record partnership for any wicket in test cricket with Jayasuria will not be broken for long, long time to come. • This is the example of an argument whose two premises appear before the conclusion is stated after ‘and’.

16. Contd… C. (1) MuttiahMuralitharan has taken more Test wickets than anyone in the history. When he retires, he will leave a mark that will not be surpassed because (2) it is improbable that any other bowler in the post-modern era will have the lasting power to breach the 700-wicket mark. • This is an example of an argument, whose conclusion is sandwiched between two premises. • Moreover this is example of an argument whose conclusion may or may not be true only the future will tell.

17. Contd… • In the same world in which more than a billion people live at level of prosperity never previously known, roughly a billion other people struggle to survive on the earth purchasing power equivalent of less then one U.S. dollar per day. Most of the world’s poorest people are undernourished, lack access to safe drinking water or even the most basic health services and cannot send their children to school. According to Unicef, more than 120 million children die every year – about 30,000 per day – from avoidable, poverty-related causes. • This report is deeply troubling – but there is no argument here.

18. Thank You