PHIL1110 Lecture Notes - Lecture 2: Deductive Reasoning
Arguments
1.1. What is critical reasoning?
1.1.1. What is this course about? THINKING IN SLOW MOTION
This is a course about showing your working ... not jumping to conclusions. I want to do this:
(1) by enhancing your analytical skills; and
(2) developing your ability to communicate your ideas.
Our fundamental tools for this are:
REASONS! Question: What are reasons?
Reasons tell us why ...? • But why what?
Question: When do we use reasons? What kinds of situation? And how do they work? What do they do?
Here are three types of situation where reasons are used:
(1) Arguments (2) Decisions
(3) Explanations
1.1.2. What is an argument? Suppose you believe that the theory of evolution is false.
Suppose you want to persuade your friend that this is the case. Question: How would you do this?
Answer: You should make an argument!
Example 1. One might argue as follows:
(1) I saw a Youtube clip that said evolution was false.
4
(2) Everything on the internet is true. (3) So, evolution must be false.
This is an example of an argument.
Question: Is it a good argument?
No ... one of the premises (we’ll define premises soon) is clearly false.
Definition 2. An argument is a passage of reasoning used to establish some proposition,
known as the conclusion.
Definition 3. A proposition is something that can be either believed or disbelieved, true
or false.
Question: What is a passage of reasoning? It has two ingredients:
1. (1) Reasons - these are just more propositions; and
2. (2) ... something which pushes us from the premises to the conclusion (this is
trickier).
The following distinction can give us a feel for this. There are two main kinds of argument:
find more resources at oneclass.com
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Document Summary
This is a course about showing your working not jumping to conclusions. I want to do this: (1) by enhancing your analytical skills; and (2) developing your ability to communicate your ideas. Here are three types of situation where reasons are used: (1) arguments (2) decisions (3) explanations. Suppose you believe that the theory of evolution is false. Suppose you want to persuade your friend that this is the case. One might argue as follows: (1) i saw a youtube clip that said evolution was false. 4 (2) everything on the internet is true. (3) so, evolution must be false. No one of the premises (we"ll define premises soon) is clearly false. An argument is a passage of reasoning used to establish some proposition, known as the conclusion. A proposition is something that can be either believed or disbelieved, true or false.
