Concepts of argument and critical thinking; For the purpose of knowledge, We shall be looking at the basic concepts in Arguments and Critical Thinking, namely, logic, proposition, and arguments. This opening session is quite important because our understanding of these concepts will aid our grasping mettle in life. We shall also be looking at how to analyze arguments, premise- indicators and conclusion-indicators.
The word logic can be used in different ways. It can be used to describe the totality of all laws guiding the human thought since we are rational beings whose thinking processes are based on certain principles. In strict, technical and professional sense, however, “logic is that branch of philosophy that deals with the study of the basic principles, techniques or methods for evaluating arguments”. This definition shows that logic as a branch of philosophy attempts mainly to distinguish between good and bad arguments. It also can be defined as “the study of the methods and principles used to distinguish correct from incorrect reasoning”. Thus, basically, logic is “the study of the nature and characteristics of good reasoning, and the differences between good (“correct”) and bad (“incorrect”) reasoning.
A proposition can be used to refer to the content of a meaningful declarative sentence or the pattern of symbols, marks or sounds that make up a meaningful declarative sentence. It “asserts that something is (or is not) the case; any proposition may be affirmed or denied”. A proposition has the quality or property of being true or false, implying that every proposition must be either true or false. This is why a proposition is sometimes referred to as “truthbearers”. Truth and falsity therefore apply always to propositions. Copi et al distinguish between propositions and sentences. They point out that sentences are the means by which propositions are asserted. In other words, “Two different sentences, consisting of different words differently arranged, may have the same meaning and be used to assert the same proposition”. For example, the following are two different sentences that make the same assertion: “Goodluck Jonathan won the 2011 Presidential Election in Nigeria” and “The 2011 Presidential Election was won by Goodluck Jonathan”.
We must add here that the terms “proposition” and “statement” have been used interchangeably by some logicians. Therefore, the term “statement”, though not an exact synonym of proposition, “is used in logic in much the same sense. Some logicians prefer statement to propositions, although the latter has been more common in the history of logic”.
There are simple as well as compound propositions.A simple proposition makes only one assertion, while a compound proposition contains two or more simple propositions. In other words, you assert more than one proposition in a compound proposition. For example:
⇒The largest country in the world is the third most populous country in the
⇒The man who won the 2011 Presidential Election is the President of Nigeria.
⇒By the 1830s the white men were the dominant race in the Hunter Valley. Most of the prime land along the main river frontages had been taken up for crops and cattle and settlers were moving into the back country north and west of the Hunter. After 1830 most resistance by the Kooris was passive, although there were spasmodic outbreaks of violence. Nevertheless, the two races could not live completely apart and growing contact was inevitable.
⇒Turning local government areas to development areas will maximise growth. We say this because turning local government areas into development areas will depoliticise development, as suspicions of neglect due to fears of ethnic domination in various states will diminish and support for the party at the helm of affairs at the state capital or centre will also cease to be the basis for the provision of amenities in local government areas. (Adapted from AfricanGuardian).
Examples (i) and (ii) are simple propositions, while (iii) and
(iv) are examples of compound propositions.
The term ‘argument’ can have a dual meaning. In ordinary discourse, it connotes a quarrel or disagreement, whereas in logic – thatis, in the technical sense – an argument is a sequence of statements, ‘declarative sentences’ or propositions, in which one part known as the conclusion is claimed to follow from the others called the premises. In clear terms, therefore, an argument is any group of propositions of which one is claimed to follow from the others, which are regarded as providing support or grounds for the truth of that one.That means that an argument is not just a mere collection of statements. An argument has a structure which is defined by the terms ‘premises’ and ‘conclusion’ and the nature of the relationship between them.
The conclusion of an argument is that proposition which is affirmed on the basis of some other propositions, which serve as justification for the acceptance of the conclusion. These other propositions, which go by various names such as evidence, grounds, or reasons, are more professionally called premises. In an argument, therefore, the premises are intended to provide sufficient grounds for the acceptance of the conclusion.For an argument to be present, “there must be some structure within the cluster of propositions, a structure that captures or exhibits some inference. This structure we describe using the terms premise and conclusion. Thus, the premise is a proposition used in an argument to support some other proposition, while the conclusion is the proposition in an argument that the other propositions (that is, the premises) support. Where there is no relationship whatsoever between the putative claim or conclusion and the reasons given for its acceptance, then there is no argument.
An argument may have two sentences where the first sentence serves as the basis for accepting the other which is the conclusion. In other words, the premise and the conclusion may be stated separately, each in a separate sentence. For example:
- Donte Drumm has not been convicted of the crime of murder. Therefore, any statement indicting him of the murder should be jettisoned as mere insinuation.
- Okorocha is a politician who has recorded great success at the state level. Therefore, he will win the presidential election in
Sometimes, both the premise and the conclusion may be stated in the same sentence. For example:
- 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.
- Since it was clear that Daryll was not in London when her husband died, it would be wrong to bring her to court for questioning.