Chapter 1/Lecture 1
The Nature of Logic and Reasoning
1. Logic is the discipline which studies reasoning/argument/argumentative discourse
(hereafter RAD) and RAD is the type of discourse which tries to prove that a conclusion is
true by appealing to evidence.
2. RAD consists of two parts or components: a) premises and b) conclusions.
3. Premises are evidence claims adduced in support of other claims while the claims on behalf
of which premises are adduced are conclusions.
4. For example, “All people are mortal (premise 1), Socrates is a person (premise 2),
therefore, Socrates is mortal (conclusion),” is an instance of RAD.
5. Logic and RAD are important at the university because students must be able to reason
well, at least in their area/s of specialization, if they are to succeed in an academic or
professional career.
6. The other type of discourse which is important at the university is informational discourse
(hereafter ID).
7. ID is the type of discourse which tries to describe states of affairs in the empirically
observable world (the world we can access via our five senses, either unaided or aided by
enhancers like microscopes, telescopes, etc.) correctly or truly. For example, “Justin
Trudeau is Prime Minister of Canada,” and “Toronto is located on the north shore of Lake
Ontario,” are correct/true informational claims about two states of affairs in the empirically
observable world.
8. ID is important at the university because students must accumulate a lot of information, at
least in their area/s of specialization, if they are to succeed in an academic or professional
career.
9. There are many other types of discourse, most of which, unfortunately, are marginalized
or ignored at the university. For example, skill in narrative or story-telling discourse is
extremely important for success in an academic or professional career. Other things being
equal, which person would you rather have as your dentist: a) a technically proficient
dentist who tells great stories while working on your teeth or b) a technically proficient
dentist who never says a word or is full of idle chatter while working on your teeth?
10. Unfortunately, the university does almost nothing to help students learn the fine art of
storytelling. This is shocking because the ability to tell great stories may have more “social
capital” in an academic or professional career than prowess in RAD and ID combined!
11. We cannot remedy this problem here, but we should never forget that it exists as we study
the nature of RAD and gather ID about it.
Chapter 1, The Nature of Logic and Reasoning
12. As I said in #2 above, RAD consists of two parts or components: a) premises and b)
conclusions. As I observed in #3 above, furthermore, premises are evidence claims adduced
in support of other claims and conclusions are the claims on behalf of which premises are
adduced.
13. In other words, the two parts of RAD are (and, indeed, must be) claims. This raises the
question, “What are claims?”
14. Claims i) express complete thoughts as assertions (not as questions or exclamations), ii) do
not need a context in order to have meaning (though a context may supplement their
meaning), and iii) are either true or false.
15. For example, “2 + 2=4,” “If you are going west, north is on your right-hand side,” and “I
am taking an on-line course this summer” are all claims because they satisfy conditions i),
ii), and iii).
16. The next thing we need to consider, consequent upon #1 and #12, is the question, “What is
evidence?” Evidence is reason/s, expressed as claims/s (premise/s), for believing that some
other claim (conclusion) is true. For example, in the RAD, “All people are mortal, Socrates
is a person, therefore, Socrates is mortal,” the evidence for the conclusion, “Socrates is
mortal,” is supplied by the claims/premises “All people are mortal” and “Socrates is a
person.”
17. Evidence is crucial to logic and what it studies---RAD—for without it, logic and RAD
would be impossible (no premises=no conclusions).
18. There are three ways to identify premises and conclusions in RAD: a) the indicator-word
criterion, b) the function criterion, and c) the evidence criterion.
19. Indicator words are words/terms/expressions which signal that a premise/s or conclusion/s
is/are about to happen. Indicator words for premises include “if,” “because,” “since,” “for,”
“given the fact that,” “in light of,” “in view of.” “seeing that,” etc. Indicator words for
conclusions include “then,” “therefore,” “thus,” “hence,” “consequently,” “it follows that,”
“so,” etc.
20. For example, in the RAD, “Since I didn’t see it, therefore I don’t believe it,” the premise
is the claim that follows “Since” (“I didn’t see it.”) while the conclusion is the claim that
follows “therefore” (“I don’t believe it.”).
21. Indicator words are an easy way to identify premises and conclusions in RAD. However,
we do not need to use any indicator words in which case it follows that we cannot always
rely on them to identify premises and conclusions. Another way to identify premises and
conclusions is needed. The second way to identify premises and conclusions in RAD is the
function criterion. According to it, the function of premises is to provide evidence for a
2
Chapter 1, The Nature of Logic and Reasoning
conclusion/s while the function of a conclusion/s is to state the claim/s which premises
purport to show is/are true.
22. For example, in the RAD, “I didn’t see it; I don’t believe it,” there are no indicator words
for the two claims, “I didn’t see it,” and “I don’t believe it.” So, which of these claims is
the premise and which is the conclusion? The indicator word criterion cannot help us
because there are no indicator words in the RAD. According to the function criterion, we
can determine which claim is the premise and which is the conclusion by determining the
function or role each plays in the argument. The function of the first claim is to provide
evidence for the second claim while the function of the second claim is to state what the
first claim purports to show is true. Since this is the function of premises and conclusions
respectively, it follows that the first claim is the premise and the second claim is the
conclusion in the argument.
23. While we do not need a third criterion for identifying premises and conclusions in RAD,
there is a such a criterion: the evidence criterion. According to it, premises are claims in
RAD which do not need evidence to prove that they are true while conclusions are claims
in RAD which do need evidence to prove that they are true.
24. For example, in the RAD, “I didn’t see it; I don’t believe it,” no evidence is required for
the first claim. If you say you didn’t see something, no one is likely to demand evidence
why you did not see it. Even if you did not see a red light and went through it while driving
a vehicle, the police officer who stops you for going through a red light is not likely to ask
you why you did not see the red light. What matters is that you went through the red light,
were apprehended by the police officer for so doing, and are now issued a ticket for
committing a traffic violation. Thus, “I didn’t see it,” is a premise in the argument. On the
other hand, “I don’t believe it,” is a claim which needs evidence to support it. If you tell
somebody that you don’t believe something, unless what you don’t believe is patently
unbelievable (e.g., “I don’t believe that Justin Trudeau is the Prime Minister of Canada.”),
chances are the other will ask you why you don’t believe it. In other words, the other
recognizes that your claim, “I don’t believe it,” needs evidence to prove that it is true in
which case, “I don’t believe it,” is the conclusion of this argument.
25. In addition to RAD, there is what some people call “argumentation.” What is the
relationship between RAD and argumentation? Simply put, argumentation is RAD in
which several parties are arguing about the same issue or topic of concern and each is trying
to prove either that the same conclusion is true or, more likely, that a different conclusion
is true.
26. For example, if two people are involved in the RAD, “I didn’t see it; I don’t believe it,”
and one of them is trying to prove that this argument is a good argument, i.e., that the
premise, “I didn’t see it, is both relevant and sufficient to prove that the conclusion, “I don’t
believe it,” is true, while the second party is trying to show that the argument is a bad
argument, i.e., that the premise, “I didn’t see it,” is neither relevant nor sufficient to prove
that the conclusion, I don’t believe it,” is true, then this is a case of argumentation.
3
Chapter 1, The Nature of Logic and Reasoning
27. In so far as it is concerned with reasoning, the focus of this course will be on RAD where
there is only one party involved in identifying its parts (premises and conclusions) and
evaluating it to determine whether it is a good or bad argument, i.e., you or your writing
group. If there is disagreement in a writing group about identifying the parts of an argument
or evaluating it, then the group must work towards consensus so that all the members
ultimately agree, i.e., act as one party.
Sample Exercises 1
Indicate whether the following statements are true or false. The answers are supplied at the
end of Sample Exercises 1:
“Wow!” is a claim.
“How do I get to Canada’s Wonderland?”, is a claim.
“Seeing is believing because…” is a claim.
RAD may have premises but no conclusion.
The evidence for the conclusion in the argument, “Seeing is believing because,
generally speaking, whatever we see we believe,” is presented by the claim,
“[G]enerally speaking, whatever we see we believe.”
6. All one needs to succeed in an academic or professional career is lots of information
about one’s areas/s of specialization and the ability to argue well about it/them.
7. The conclusion in the argument, “I’ll vote for you because I believe that you are the
best candidate,” is the claim, “I’ll vote for you.”
8. “2+2=1+1+1+1, 4=1+1+1+1, if two things are the same, whatever is true of one is true
of the other, therefore 2+2=4,” is an example of RAD.
9. Without evidence, there can be no RAD.
10. Claims like “9x9=81,” and “The square of the hypotenuse of a right-angled triangle is
equal to the sum of the squares of the other two sides,” are examples of ID.
1.
2.
3.
4.
5.
Answers (Explanations are provided for more difficult questions.):
1, False; 2, False; 3, False (It does not express a complete thought.); 4, False; 5, True; 6, False
(Fluency in informational discourse and RAD are necessary, but not sufficient, to succeed in an
academic or professional career.); 7, True; 8, True, 9, True, 10, False (Neither claim describes a
state of affairs that is empirically observable.).
Sample Short Writing Assignment: In one half-page paragraph (single-spaced, 12-point font,
no word count), summarize Chapter 1/Lecture 1:
Logic is the discipline which studies reasoning/argument/argumentative discourse (hereafter
RAD). RAD consists of two parts: premises and conclusions, both of which are claims. Claims a)
express complete thoughts as assertions, b) do not need a context to have meaning, and c) are either
true or false. Premises are claims which offer evidence for conclusions while conclusions are
claims which need evidence, as offered by premises, to support them. Premises and conclusions
can be identified by the indicator, the function, and/or the evidence criteria/on. Without evidence,
4
Chapter 1, The Nature of Logic and Reasoning
logic and RAD would be impossible since there would be no premises, in which case there could
be no conclusions. RAD is important at the university because it is one of the types of discourse
students need in order to succeed in an academic or professional career.
Sample Exercises 2
Indicate whether the following claims are true or false. The answers are at the end of Sample
Exercises 2. I’ve given you some assistance with the harder questions:
RAD must have premises but it doesn’t need a conclusion.
Premises do not need evidence to support them while conclusions do.
In English, ‘because’ always indicates, “Here comes a premise.”
In English, wherever there is an “if,” a “then” is at least implied.
Using the function criterion to identify the parts of the RAD, “I can’t hear what you are
saying; you shouldn’t bother me,” the conclusion is “I can’t hear what you are saying,”
while the premise is “[Y]ou shouldn’t bother me.”
6. Using the evidence criterion to identify the parts of the RAD, “Joe Biden is the President
of the US; he recognized better than Donald Trump that the COVID-19 pandemic is a great
opportunity for doing things differently,” the first claim is the conclusion while the second
claim is the premise.
7. The following is an example of argumentation: “My tire has a leak in it because it is flat.”
8. The claim that needs evidence to prove that it is true in the RAD, “I don’t like ice cream
because it doesn’t make my mouth water,” is “I don’t like ice cream.”
9. If an argument has indicator words for both its premises and conclusion, then the indicator
word criterion would be the easiest way to identity its parts.
10. The function and evidence criteria can be used to identify the parts of an argument, whether
it has indicator words or not.
1.
2.
3.
4.
5.
Answers:
1, F; 2, T; 3, F (‘Because’ in English can indicate several things, including a causal connection,
e.g., “The lights go on because I flipped the switch;” however, this example is not an argument in
which case ‘because’ here does not indicate, “Here comes a premise.”); 4, T; 5, F (The conclusion
is “[Y]ou shouldn’t bother me” while the premise is, “I can’t hear what you are saying.”]; 6, T; 7,
F (There is an argument here but only one party is involved.); 8, T; 9, T; 10, T.
Sample Short Writing Assignment: In one paragraph (one-half page, single-spaced, 12-point
font, no word count), describe the differences among the indicator word, function, and
evidence criteria for identifying the parts of RAD:
The two parts of RAD (reasoning/argument/argumentative discourse) are premises and
conclusions. Premises are claims which try to prove that conclusions are true while conclusions
are claims which state what RAD is trying to prove is true. There are three criteria to identify the
two parts of RAD: the indicator word, the function, and the evidence criteria. According to the
first, premises are claims which begin with words/terms/expressions (hereafter WTE’s) like “if,”
5
Chapter 1, The Nature of Logic and Reasoning
“because,” “for,” “since,” etc. while conclusions are claims which begin with WTE’s like “then,”
therefore,” “thus,” etc. According to the second, the role of premises is to provide evidence which
tries to prove that conclusions are true while the role of conclusions is to state what premises try
to prove is true. According to the third, premises are claims in RAD which do not need evidence
to prove that they are true while conclusions are claims in RAD which do.
6