Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
Introduction to Logic
Philosophy 2045.11
Spring Semester
Class time: Wednesdays, Fridays 11:10 – 12:25.
Room: Wednesdays: Monroe 115, Fridays, Monroe 250.
Professor: Michele Friend
CRN: 90169
Office and office hours: Rome 453 Fridays 1:00 – 2:00, or by appointment.
Office telephone: (202) 994-5002. I do not reliably check the voice mail.
e-mail: michele@gwu.edu.
Logic Tutor: Derek Lee
Office: Foggy Bottom Campus, Academic Building, fifth floor T510A
Office hours: TBA
E-mail: logic@gwu.edu
Required texts: Tomassi: Logic,
Damer: Attacking Faulty Reasoning: A Practical Guide to Fallacy-Free Arguments
Blackboard: The course syllabus, and some other materials will be available on
blackboard.
Grading: Attendance
5%
Assignment I:
10 %
Assignment II: (Presentation and questions): 10 %
Assignment III:
10%
In class test:
25 %
Final Exam:
40 %
Total:
100%
There is up to a bonus of 5 % for those who do well on the Learningguild certificate
in reasoning and expression. This is the only opportunity to “make up marks”.
I should like to encourage you to take the 3 hour examination in reasoning and
expression offered by the Learningguild. The examination is not yet scheduled. As soon
as I know the date and the time, and have booked a room, I shall let you know.
The examination is set by the Learningguild which is affiliated with the
University of Australia. It is run by John Howes who is a Rhodes Scholar, taught
philosophy at the University of Melbourne and was chair of the philosophy department of
the University of Cape Town. The examinations have been running for a while, and they
are internationally recognized. The web site for the guild is:
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Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
www.vicnet.net.au/~learngld. On that web site, you can see past examinations, hints
about study for the examination etc.
Your reward for taking the examination: Taking the examination is a learning
experience. It will make you more aware of how you express yourself, and how you
write. Clear writing is increasingly important in higher-level jobs. Clear writing is also a
sign of clear thinking, and this is important in logic. The examination is not restricted to
students of this class, or to students of GW. If you know of anyone who is interested in
taking the examination, then please have that person get in touch with me. After writing
the exam, you will receive detailed comments and a certificate (provided you pass). You
can gain up to 5% bonus marks on your final grade for the Introduction to Logic course.
You will be given 5% if you are awarded an A grade, 4% for a B grade, 3% for a C, 2%
for D, 1% for F. 5% is enough to make a direct ‘signed-letter’ difference on your final
grade. For example, 5% will make the difference between a B and a B+. Regardless of
the grade advantage, taking the examination will make an indirect difference, since you
will have improved your writing abilities, and these will be important on the final
assignment and the final examination for the course, and for the rest of your life.
The cost of taking the examination is $80 American dollars. Payment can be made
by check or cash. Checks should be made out to Michele Friend, and given to me at the
examination.
If you are interested in taking the examination please send me an e-mail to this
effect. Sending me an e-mail expressing interest is not binding. However, it will make the
logistics easier if I have approximate numbers.
Grading policies and attendance:
I am not responsible for ‘getting you through the course’, or ensuring that you
‘get an ‘A’’. That responsibility falls on you. I am here to assess your performance and
understanding of the subject matter covered in class. Your understanding might go
beyond what is discussed in class. For greater understanding you need to do some
independent thinking, or some research.
To pass the course, you need 45 %. Letter grades are distributed as follows: 95 –
100: A, 90 – 94.5: A-, 85 – 89.5: B+, 80 – 84.5: B, 75 – 79.5: B-, 70 – 74.5: C+, 65 –
69.5: C, 60 – 64.5: C-, 55 – 59.5: D+, 50 – 54.5: D, 45 – 49.5: D-, 0 – 44.5: F.
Assignment 1 is due in class, or can be handed in before the relevant class. If you
are handing an assignment in early, then please ask the executive aides in Phillips, on the
5th floor, to put it in my mail box. Late assignments are not accepted. No grade is given in
the case of a late assignment or an assignment not handed in. You simply lose the 10%,
similarly if you do not turn up to give your part of the presentation for assignment II.
I distinguish between assignments (which are handed in, given a grade and count
towards your final grade) and homework (which includes reading and exercises, but is
not graded). Homework exercises are practice exercises for you. They are not handed in.
They are not graded. Often, the solutions to the homework exercises will be discussed in
class. If you wish to hand these in to verify that you have done the exercises correctly,
then you may do so. Hand them in to my mail box in the philosophy department (5th floor
Phillips) or to me in class. I will hand them back as promptly as is convenient to me.
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Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
When grading exercises in formal logic a mark is deducted for each mistake. For
example, a tree proof might be marked out of 3. For each mistake a mark is deducted,
including what you might mistakenly think of as ‘small mistakes’ in observing
conventions regarding notation, or conventions regarding setting up a proof. In contrast,
when assignments concern critical thinking questions, there are no absolutely right or
wrong answers. I look for good arguments in support of the claims you make. If you
make good and plausible arguments for your claims in assessing arguments, then you will
have a satisfactory, or even good, grade. If you show some originality and a high degree
of sophistication in your analysis, then you will receive an excellent grade. When
grading, I reserve the right to err on the side of generosity. Grades assigned are not
negotiated, in the interest of fairness to all the students. However, please check I have
added the grades on assignments correctly.
Logic is not like other arts subjects. You have to be organized, meticulous and
you must keep up with the homework and with the reading. If you do not do the reading
before class, there is a risk that you will not understand the material presented in the
class. This will be particularly true of the material we cover from the Tomassi book. If
you have missed the first few classes, then make sure you get the notes from a fellow
student. In this class I do not ask you to read many words, but I do ask that you read them
carefully.
It might be useful to form study groups, where you help each other with the
homework. However, be careful that these do not degenerate into sessions where one
person does the work, and the others copy. If you form a work group, make sure that all
the people in the group understand the solutions. If you do one of your official graded
assignments with someone else, please write this at the top of the page. This is for
reasons of academic integrity. No grades are deducted for working in groups. However,
you should all hand in different and separate solutions to your assignments. Do not just
print out several copies and sign your name at the top. If two or more people hand in a
solution set, and this is not acknowledged, and it is clear to me that they are copies of
each other, then the grade on the assignment will be split between those in the group,
similarly for individual answers. Each person in a group should write out the solutions
himself, or herself, using his, or her, own words and expressions. You may hand in
computer printed, typed, or hand-written solutions. Because of the symbols, it is often
easier to hand-write solutions. These have to be legible to me.
Attendance in class is important. Attendance is not compulsory. Incentive is
provided by the 5%. Attendance grades are calculated as follows: If you miss a few
classes at the beginning, before you are registered, then this is completely forgiven. After
having registered, then you are given slack for two missed classes. After that, for each
class missed regardless of the reason (unless it is for reasons of religious observance
(and I am notified within the first two weeks of classes)), 1% is deducted from the final
grade. I take a dim view of students missing classes around holidays. If you do book a
flight early, i.e., such that you miss some classes, then be aware that this is your choice,
and it is your responsibility to catch up and hand in assignments. You might want to warn
your parents about this, if they will be booking tickets for you.
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Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
Difficulties with the course:
If you are falling behind, or feel that you do not understand: do not panic. If you
are feeling overwhelmed or behind, it is a bad idea to avoid doing the work, coming to
class, and coming to see me during office hours. It is a good idea to see me, see the logic
tutors, come to class, read the assigned reading again, more carefully, ask your friends in
the class to help you, do extra homework problems and continue to hand in assignments,
however sketchy. If you come to classes, see me during office hours, and see the logic
tutors, you can get 6 hours and 30 minutes logic instruction a week. So the department
provides ample opportunity for you to do well in the class. The responsibility for doing
well falls on you.
A nice point about the class is that we start with the harder material, and then
move to easier material, so the pace is the opposite of most of your classes.
The Logic Tutor:
Be aware that the logic tutor position is held by an undergraduate student who
has shown a good understanding of logic in both this, and the Symbolic Logic class.
Thus, the tutor is your senior, but is not an expert in logic. The tutor is not responsible for
‘getting the students through the course’, or in insuring that they ‘get an ‘A’’ or doing the
assignments with you.
The tutor is there to effectively extend my office hours; to help you in better
understanding logic generally, and as a second person to consult about logic. The tutor
may offer an explanation which is different from my own. This might or might not be
helpful to you. Often it is helpful to hear why a rule is the way it is from a different
perspective, or put in a different way. It might also be helpful to rehearse the use of new
words with someone who knows them well, or to discuss your projects in informal
reasoning.
The tutor will inform me of his office hours once he knows what these are. The
philosophy department pays him for those hours. If you want to meet with him during
other hours, you will have to come to some private arrangement with him. I can also
supply names and e-mail addresses of other students who can give help privately (i.e.,
you have to pay them, and come to your own arrangement with them). Note that since the
tutor is a student also, he, too, has to hand in papers and take exams, so don’t leave your
problems until the last minute. Nip problems in the bud. As soon as you feel shaky about
your knowledge, address it. Part of your broader university education consists in being
able to accurately assess your own level of knowledge, and learning to responsibly
address any problems.
There are no prerequisites for the course. This is a pre-requisite for the symbolic
logic course (phil. 121).
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Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
Course description:
There are two components covered in the course. One is informal reasoning and
critical thinking. The other is formal logic.
The formal system we shall be studying is called propositional logic. Roughly, a
proposition is the content of, or what is referred to by, a declarative sentence.
Grammatically, we can test for propositions by asking ourselves if it would be suitable to
put the proposition after the word ‘that’ in an English sentence. An example of a
declarative sentence is: "Thomas is tall". Grammatically, it makes sense to say “…that
Thomas is tall.” Two different sentences (using different words, or words in a different
order) might refer to the same proposition. For example: "Thomas is tall" and "Thomas is
not short" are different sentences, (because they use different words) but they have the
same content. That is, they refer to the same proposition (roughly). So, a proposition
expresses a fact (roughly).
In propositional logic, we are neither interested in which particular words are used
to express a given fact, nor in what order the words are used nor in the poetry of the
sentence or whatever. All these aspects of expressions are considered to be ‘white noise’,
and we abstract away from these by assigning each proposition a letter such as p or q. We
may then join proposition letters together using logical connectives. The connectives
roughly correspond to the English locutions: “and”, “or”, “not”, “if… then…” and “if and
only if”. Joining proposition letters using logical connectives still results in a proposition,
i.e., a sentence or formula which can be either true or false. The idea behind propositional
logic is that we reason from a set of facts (the premises) to a new fact (the conclusion).
Logical reasoning guarantees that if we start with true facts, then the conclusion will also
be true. We strictly obey rules which involve the connectives to reason from the
premises to the conclusion. When we successfully construct the conclusion, using only
the rules of deductive reasoning from the premises, we form a logically valid argument.
The notion of valid argument is central to the study of formal logic.
In studying formal propositional logic, we shall learn to translate arguments
written in English into symbolic notation. We shall then learn how to construct formal
proofs showing the validity of arguments. A formal proof is one where only certain
approved manipulation rules are allowed. The rules allow us to remove or introduce a
logical connective into an expression which might, or might not, include other
connectives. These proofs are not mechanical. So, I cannot give you absolute rules about
which inference rule to employ when. But, I can give you rules of thumb, which are hints
about what to try to do. I shall try to be as explicit as possible about rules of thumb
throughout this part of the course. Making a proof might require several attempts.
After mastering various proof techniques, we shall learn the specific relationship
between truth and the logical connectives. In this part of the course, we learn about truth
tables. These are mechanical. Finally, we shall spend a little time exploring the
relationship between the tables and the syntactic proofs we learned earlier through truthtrees. These are also mechanical proofs testing for the validity or invalidity of a formally
expressed argument. Assignment 1 and the in class test concern the formal part of the
course. Assignment 1 will be handed out in class, a week before it is due. The test will
occupy a class period.
The other component of the course is called 'informal reasoning' or 'critical
thinking'. Informal reasoning is not about proof, but about supporting conclusions with
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Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
plausible premises. A set of premises might support a conclusion well or poorly. In
particular, we shall be concerned with fallacies of reasoning which trick you into thinking
that a conclusion is well supported, when it is not. To understand what fallacies are in
general, first distinguish between someone who merely manages to persuade you to say
or do something, as opposed to someone giving you a perfectly good reason to do
something. The first works temporarily, but you might come to regret your decision or
action quite quickly. The second is longer lasting, and revising a decision is not a matter
of detecting a trick (fallacy) but of deepening an argument – usually looking for
background assumptions and assessing these, so, up-dating, confirming or disconfirming
information.
For example, a salesperson might use flattery to persuade you to purchase an
item. He, or she, might say: "anyone of your taste and integrity will see what good quality
the item is. Therefore you should purchase the item." The salesperson has not argued that
the item itself is of good quality, nor has he, or she, given a direct reason for thinking that
the item is of good quality, or that it will meet your needs. The salesperson might have
been persuasive and successful, by appealing to your vanity, but he, or she, has not given
you a good reason for buying the item.
In the critical thinking component of the course, we shall look at a number of
different fallacies. These are grouped under five general headings: structural fallacies,
fallacies of relevance, fallacies of acceptability, fallacies of sufficiency and rebuttal
fallacies. Avoidance of all these fallacies in a written essay or presentation results in
a concise, well argued, sophisticated argument, which should be persuasive for good
reasons, since the premises really do support the conclusion.
We shall also discuss argument protocol, a little about the psychology of
argumentation and work on some arguments we find in newspapers, on the internet or in
books. A pivotal distinction to draw will be that between defending an opinion and
seeking the truth about an issue. The former is characterised by an unwillingness to
change one’s mind. The latter is characterised by a willingness to change one’s mind in
the light of a better argument for the opposing view or better evidence for that view.
There are three graded pieces attached to the critical thinking aspect of the
course. One is based on presentation and “found’ examples you bring to class. For the
presentations you will be put into groups. You will each have two tasks. One is to present
to the class examples of a particular fallacy to the rest of the class during the designated
class day. The other is to bring to class, for another group, one example of a found fallacy
for the class and the presenting group to guess which fallacy (of the general category) the
example is meant to represent.
More specifically, I shall begin the class by discussing the definition of the
general category of fallacies, and definitions of particular fallacies falling under the
category. This will take 10 – 15 minutes. The students in the ‘presenting group’ will then
take it in turn to present found examples of the fallacy they have decided to present. Note
that not all of the particular fallacies in a general category will be presented. Sometimes
there are more specific fallacies under a category than there are members of the
presenting group. When presenting a fallacy, you will be asked to present two to four
examples of your fallacy which you have found, either in a newspaper, in a text book, in
a novel, on the internet, or anywhere such that the source can be verified. You may not
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Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
use a fallacy from a web-site on fallacies. Find your own examples from sources that do
not intend to illustrate a fallacy.
That is, you may not just make up an example. Do not take examples from
the Damer text. Do not take them from the Stanford encyclopedia of philosophy, etc.
Your fellow students will have already read the text. They do not need for you to read it
out to them again. Overhearing a conversation is also not verifiable enough. Collecting
examples will take time, so start on this early.
Present the examples written up on the board or on an overhead transparency, or
by power-point presentation. For those of you using power point: you will be given a
maximum of 5 minutes at the beginning of class to set up your power point. You are
welcome to come to class early. After 5 minutes, if the power point is not working, then
use a different means of presentation. In the presentation, explain why the examples are
examples of the chosen fallacy. Choose a mixture of easy examples and more difficult
examples. The difficult examples are occasions to explore with the class the limitations of
the fallacy. The difficult examples occur when it is not clear that a premise to an
argument is being fallaciously used. There are no absolute or right or wrong answers in
informal reasoning. Calling a premise fallacious is a judgment-call, the judgment often
has to do with the set of preconceptions held by a group of people. What counts as
commonsense, or obvious to one group of people, is not obvious to another group. You
will know this from travelling, talking to people from different cultural backgrounds or
from history. As such, there is room for debate as to whether a given premise really is
fallacious. Choose some examples which you think will be less obvious, given the makeup of the class. To help with this part of the discussion, as a suggestion, you might find
examples about which you are not sure yourself if they constitute a fallacious argument
or not. You can also look in various journals of critical thinking or informal reasoning to
see where there is room for controversy. This is not quickly done. You will need time to
find appropriate journal articles, digest them, and apply them to your examples. The
whole group together should take about 20 minutes to present their examples. You should
stand in front of the class to give this presentation.
On the occasion of a presentation of examples by a group of class members,
(say, group A) there will be another group (say, group B) responsible for bringing to
class examples under the general category of fallacies discussed that day by group A.
You will very quickly present your fallacy, give the source, and ask the class and the
“experts” to guess which fallacy it is that is represented in your example. The class, then
the experts, will guess, and we’ll have a very brief discussion. Note that these examples
will come from the general category, not necessarily from the list of examples prepared
by the presenters. For the final examination, you are responsible for all of the fallacies of
reasoning in the Damer text (with a few exceptions amongst the structural fallacies).
We shall be strict about the timing for your presentation of fallacies. You will
need to allot time to meet and discuss the examples and fallacies amongst yourselves well
before the presentation. Make sure you have enough material, can deal with examples in
a sophisticated manner, and can stay within the timing. Groups will be assigned in the
third week of classes.
For assignment III, you will have written a, roughly, 500 - 800 word argument
during the first two weeks of classes (with suitable adjustments made for people joining
the class late). At the end of the semester, you will be asked to write another (roughly)
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Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
500 - 800 word argument for the same issue. You will be graded on the quality of the first
paper, the difference between the first and last paper, and on the quality of the last paper.
Choose one from the following list of conclusions to argue for. (a) Climate change poses
no long-term environmental, economic or social problem. (b) It should be made illegal to
raise “battery chickens”. (c) Everyone (in the country/ state/ city/ county (choose one))
should be allowed to carry fire arms. (d) Female circumcision is a personal choice which
should be left to individuals. (e) Learning disabilities should not be given any special
accommodation at university. (f) In the (country/ state/ municipality (choose one)) the
legal drinking age should be 16 years. (g) There should be a maximum salary set at, say,
$200,000 per year, for everyone in the world/ country/ state/ (choose one or) company
(imagine a large company, employing at least 1000 people). (h) We should be given
quotas for our ecological footprint, and be fined if we exceed it. (i) There are very few
real democracies left. (j) There are superior and inferior people. (k) Corruption is a
normal and natural aspect of all modern politics at all levels. (l) Technology is causing
humans to evolve biologically. (m) It should be made illegal for people to sleep on the
street. (n) More roads should be built.
Aims:
By the end of the course, you should have a good working knowledge of formal
proofs in propositional logic. In fact, it will be hard to pass the course without this. You
should be able to translate sentences from English into the symbolic notation used for
proofs in propositional logic. You should be able to give a semantic analysis of sentences
and arguments. You should have some knowledge of some common fallacies, and be able
to identify these in examples. You should have sharpened your critical and argumentative
skills. For example, when you encounter a fallacy, you should be able to help your
opponent to fill in background or deepen his, or her, argument. Finally, you should have a
grasp of the distinction between fallacious arguments, good arguments and logically valid
arguments: the merits and demerits of each. You should be writing in a more discerning
manner.
Learning objectives: “Learning objectives” reflects what administrative evaluators of
the quality of the courses at GW recognize as important indicators of the excellence of
your education, hence the bullet-points.
On successful completion of this course, you should have acquired a range of knowledge,
abilities and formal and informal logic skills. You should be able to demonstrate:
 Knowledge of a number of fallacies of reasoning,
 Knowledge of several technical terms used in formal logic,
 Knowledge of logically valid inference moves,
 Comprehension of the terms used in formal reasoning,
 Knowledge of definitions of fallacies of reasoning,
 Examples of fallacies of reasoning,
 Your ability to apply rules of inference in an argument,
 Your ability to evaluate informal arguments for their strengths and weaknesses,
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Phil. 2045.11 Course Syllabus, Spring 2014.
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Professor Michele Friend
You should also be able to:
Construct good arguments,
 Interpret sentences in English, and translate them into the formal language of
propositional logic,
 Refute poor arguments,
 Use truth-tables to evaluate the validity of an argument,
 Use truth-trees to evaluate the validity of an argument,
 Articulate your understanding of key concepts in logic such as: validity,
soundness, consistency, semantics and syntax,
 The ability to improve poor informal arguments.
Time Budget: You should break down your study time roughly as follows:
Lectures: 28 X 75 mins. = 2100 mins., 2100 ÷ 60 = 35 hours. So the lecture time
for the semester is 35 hours.
Reading for class: 15 hours
Daily homework: 15 hours
Assignments: 20 hours
Study for the mid-term test and the final examination: 15 hours
Total: roughly 100 hours.
Academic integrity:
In 1995, the students of George Washington University committed themselves to
high standards of academic integrity by passing a 'Code of Academic Integrity'. By
attending George Washington University you are obliged to follow this code. The 'Code
of Academic Integrity' can be found in the "Student Planner and Handbook" and also in
the "Guide to Student Rights and Responsibilities". The latter can be obtained in the
office of the Dean of each school, and in the office of the Dean of Students. You are
expected to be familiar with the Code, to understand what constitutes dishonest academic
behavior, and to avoid any such behavior. Sanctions for offences include failure of an
assignment, failure of a course, suspension from the university for a specified amount of
time and expulsion from the university.
Instructional Modifications for Students with Disabilities:
Any student who feels that he, or she, might need accommodation because of a
disability should contact the Disability Support Services office. The telephone number is:
202 994-8250. The office is DSS in the Marvin Centre Suite 242. You have to contact
them to secure eligibility and to coordinate accommodations. At the student’s request,
DSS prepares and individualized letter to professors which testifies to the nature of the
student’s disability in very general terms and documents the need for auxiliary aides and
services and/or academic adjustments. Students are encouraged to meet with each
professor early in the semester to discuss the academic implications of disability as it
relates to the specific course and to request accommodation. For additional information
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Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
please refer to http://gwired.gwu.edu/dss/. The most commonly used sorts of service
available are extended time for tests and exams and note taking by another student in the
class. Less common is sign-language simultaneous translation during lectures. Other
services are also possible. Note that for these services to be implemented, the
documentation has to be done officially through DSS. Your teacher is not qualified to
grant you extra time, based on a disability, since not qualified to diagnose disabilities.
The University Counseling Center (UCC)
The University Counseling center (UCC) assists students in addressing personal,
social, career and study problems that can interfere with their academic progress and
success. Services for students include: Academic support and peer tutoring services. See:
http://gwired.gwu.edu/counsel/AcademicSupport. You can avail yourself of crisis
consultations by telephoning: 2029945300 (24/7). There is also a confidential counseling
service, podcast and self-help materials on the web site:
http://gwired.gwu.edu/counsel/PodCast/,
http://gwired.gwu.edu/counsel/OutreachSelfHelp/.
Should any student require any modification to the testing procedure, the seating
arrangement or access to the classroom please speak to me either after class, or during
office hours. Such matters have to be dealt with by an official procedure, for the most
part. So, it is better to warn me as soon as possible.
Security
“In the case of an emergency, if at all possible, the class should shelter in place
(sic!). If the building that the class is in is affected, follow the evacuation procedures for
the building. After evacuation, seek shelter at a predetermined rendezvous location (sic!)”
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Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
Schedule: The schedule is a rough schedule. If there is an interruption, then the
classes all get ‘bumped up’ a date. Make-up classes will be announced after the
interruption. Notice will be given in class of any changes. Homework is due in the
following class. Written assignments 1 and 3 are due two classes after they are
assigned. Assignment 2 is a presentation.
How to read the schedule: The day takes place along the horizontal line. The first
column gives the date. The second gives the reading for class. The third column tells
you what the topic is which will be covered in class. The fourth column tells you
what homework to do for the next class.
Date
15
Jan.
17
Jan.
Reading due
None.
22
Jan.
Tomassi, pp.
32 - 39
24
Jan.
Tomassi: pp.
42 – 55.
29
Jan.
31
Jan.
Tomassi: pp.
56 – 63.
Tomassi: pp.
63 – 66.
5 Feb.
Tomassi: pp.
66 – 70.
Tomassi: 74 –
82.
Tomassi: pp.
82 – 93.
Tomassi: pp.
94 – 108.
7 Feb.
12
Feb.
14
Feb.
19
Feb.
21
Feb.
Tomassi, pp.1
– 26
Topic covered
Syllabus, introduction.
Logically valid arguments.
Syntax, Semantics, the
language of Propositional
Logic.
Arguments and Sequents.
Translating into
Propositional Logic.
Introduction to natural
deduction. &I, &E, M.P.
Homework/ Assignments set
None.
Tomassi: p.26 #1 (all), #3 (all) #4
A, B, D, #6, #7.
Tomassi: p.42 # 1 (all) #3 (all).
Conditional Proof.
Tomassi: p. 53 # 2.2, 2.6, 2.8, p.
55 # 1 (all), p. 56: 2.iv. First part
of assignment 3, due 31 Jan.
Tomassi: p. 63 # 1, 2, 4, 6.
Augmentation, Theorems.
Hand in first part of
assignment 3.
The biconditional.
Tomassi: p. 63 #1.9, p. 66 #1.1,
#1.3, plus exercises handed out in
class.
Tomassi: p. 69 #1.1, 1.2. 1.4.
Negation: MT, DNI, DNE.
Tomassi: p. 82 1.2, 1.3, 1.4, 1.7,
1.8.
Tomassi: p. 100 #1.1, 1.2, p. 101
# 1.1, 1.2
Assignment 1 Handed out in
class. Due 21 Feb.
Or: VI, VE.
Reductio ad Absurdum,
Strategies for proof.
None.
Revision session: Natural
Deduction proofs.
Attendance Optional!
Tomassi: pp. Truth tables, tautologies,
122 – 143. pp. contradictions and
160 – 162.
contingent sentences,
semantic equivalence.
11
None.
Tomassi: p. 141 #1.1, 1.6, 1.8,
1.14, p.143 #1, 2. P. 163 3.1, 3.3,
3.5.
Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
26
Feb.
Tomassi: pp.
144 – 159.
Using tables to test for
validity. Comparative
method, first and second
methods only.
Truth Trees, Consistency
Trees
Truth Trees: Validity Trees
28
Feb.
5
March
7
March
19
March
21
March
Tomassi: pp.
163 – 167.
Tomassi: pp.
167 – 176.
None.
26
March
Damer pp. 52
– 65.
Fallacies of structure.
28
March
Damer pp.78
– 101.
Presentation by group 1
on fallacies of relevance.
2
April
Damer pp.
104 – 136.
Revision session.
Attendance optional.
None.
Test on material from the
start of classes.
Damer pp. 1 – Informal Arguments Good
50.
Arguments: four criteria.
Fallacies.
9
April
Presentation by group 2
on fallacies of
acceptability: Linguistic
confusion.
Damer pp.
Presentation by group 3
141 – 155.
on unwarranted
assumption fallacies.
Damer pp.156 Presentation by group 4
- 168.
on missing evidence.
11
April
Damer pp.171 Presentation by group 5
– 188.
on causal fallacies.
16
April
18
April
None.
5
April
None.
Presentation by group 6
fallacies of rebuttal.
Preparation for the
examination. Attendance
optional.
12
Tomassi: p.150 #1.4, 1.5, 1.6. p.
159 #1.1, 1.2, 1.3, 2.1, 2.4.
Tomassi: p. 167 # 1.2, 1.3, 1.4,
1.5.
Tomassi: p. 176. #1.1, 1.3, 1.5,
1.7, 1.9.
Study.
None.
Find a fallacious argument. Put it
into standard form. Explain
which category of fallacy the
fallacy belongs to.
Each member of group 4, bring
to next class a found example of
a fallacy of relevance.
Each member of group 5, bring
to class a found example of a
fallacy of linguistic confusion.
Each member of group 6, bring
to next class a found example of
a fallacy of unwarranted
assumption.
Each member of group 1, bring
to next class a found example of
a fallacy of missing evidence.
Each member of group 2, bring
to next class a found example of
a causal fallacy.
Each member of group 3, bring
to next class a found example of
a fallacy of rebuttal. Second part
of assignment 3 due 18 April.
None.
Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
After the exam
You will be able to pick up your exam booklets from the holder outside my office door
once they are graded. They should be available four days after the exam takes place. I am
not allowed to disclose your final grades to you until the registrar has published them.
There is a follow-on course from this one. It is Philosophy 121: Symbolic Logic. This
follows on from the formal reasoning we did at the beginning.
Classroom protocol:
Classroom protocol are as follows:
Mobile telephones:
Allowed at all times, except during tests, set on “buzzing” only. Text replies only.
Computers:
may be used for taking notes,
may be used for texting friends and family,
may not be used for playing games, or for other distractions (watching films, doing
homework etc) during class.
Lateness coming to class, early leaving of class: The row at the back of the class is
“reserved” for people who want to leave class early, or who come in late.
Sample Final Examination
 Answer all questions.
 The examination is out of 100.
 The number in bold to the left of the number of the question
indicates what the question is worth.
 You do not have to answer the questions in order.
Critical Thinking Questions
(14) 1. Answer one of the following two questions.
(i) What is the difference between testimony and argument? How do you asses these?
(ii) “Appeal to emotions in arguments is always wrong because emotions cloud our
reasoning.” Comment.
(16) 2. Choose four of the following fallacies. Give an example of each, and say why it
is an example of that fallacy.
13
Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
(i) Irrelevant authority.
(ii) Illicit contrast.
(iii) Appeal to self-interest.
(iv) Misuse of vague expression.
(v) Is-Ought fallacy.
(vi) Neglect of a common cause.
(12) 3. Analyse the following arguments. Put them into standard form. Say what you
think is wrong with the argument, and how you would attack it or make it into a better
argument.
(i) Sixty-six percent of all rape and murder victims are friends or former friends or
relatives of their assailants. Therefore, you are safer in a public park among strangers at
night, than you are at home in your bed.
(ii) Mother: I think it would be a good idea to encourage the kids to watch less television
and get more exercise.
Father: So, you think I have let the kids become a bunch of lazy, unhealthy television
addicts?
(iii) No matter how hard I study, I still don’t do well on the tests. I always seem to study
the wrong stuff. I guess I should not study at all, and just take the test blind.
(6) 4. Use the fallacies of argument to write a bad argument for one of the following
conclusions. (Put the name of the fallacy you think you are committing in parentheses
after you have used it).
(i) Abortion should never be allowed.
(ii) All broadcasting on television should be illegal on Wednesdays from noon to
midnight.
(iii) Smoking is good for teenagers.
(iv) Tennis should no longer be considered to be an Olympic sport.
Formal Reasoning Questions
(7) 5. Use the method of conjoining the premises and implying the conclusion to test the
following sequent for validity. If the sequent is invalid, then give a truth-value
assignment to the proposition letters which acts as a counter-example to the validity of
the argument. Also give the disjunctive normal form of the first premise.
~(P  ~Q), P  Q : ~P & Q
(6) 6. Translate the following sentences into propositional logic. Give a key.
14
Phil. 2045.11 Course Syllabus, Spring 2014.
Professor Michele Friend
(i) If Colonel Mustard has the knife, then either Miss Scarlet is in the drawing room or
Professor Plum is.
(ii) It is plainly not true that Etta James is an angel and that Robert Johnson sold his soul
to the devil.
(3) 7. Use a truth table to check if the following sentence is a tautology, contradiction or
contingent sentence. Show the table.
~((P  Q)  P)
(6) 8. Use a tree to check the validity of the following sequent. If the argument is invalid
then give a counter-example.
: (P  Q)  ~(P & ~Q)
(6) 8. Use a tree to check the consistency of the following set of sentences. If they are
consistent with each other, then give a model.
{(~P  ~Q)  R, ~P & ~Q, R}
9. Use Natural Deduction to prove that the following sequents are valid.
(4)
(6)
(3)
(5)
(6)
(i) ~(P & ~Q) : P  Q
(ii) P  (Q  R), R  S : P  (Q  S)
(iii) : (P  ~Q)  (Q  ~P)
(iv) (P  (Q  R) : (P & Q)  R
(v) P  Q, Q  S : (P  Q)  (R  S)
15
(8)
(11)
(6)
(9)
(11)