preview

Philosophy 103 Introduction To The Nature Of Logic

Good Essays
Open Document

Philosophy 103: Introduction to Logic
The Nature of Logic
Abstract: Some of the uses of logic are illustrated, and deductive arguments are briefly distinguished from inductive arguments.

I. Logic is the study of the methods and principles used in distinguishing correct from incorrect reasoning.
B. Logic differs from psychology in being a normative or a prescriptive discipline rather than a descriptive discipline.
1. I.e., it prescribes how one ought to reason; it's not concerned with how one actually does reason.
2. Logic is concerned with laying down the rules for correct reasoning.
3. Consequently, logic seeks to distinguish good arguments from poor ones.
II. How Logic helps reasoning:
A. "Practice makes better." Some …show more content…

These methods are shown here merely for purposes of illustration..
1. For example, we can draw Venn Diagrams to show the fallacy of the undistributed middle term in problem I, A discussed above.

2. Or we can show the fallacy in I, A by appealing to specific rules.
All P is Mu.
All S is Mu.
All S is P.

The term shared by both premisses is said to be undistributed because it does not refer to each and every persons in favor of higher taxes.
III. There are several kinds of logic which exhibit a kind of family relation: dialectic, multivalued logic, logic of commands, fuzzy logic, etc.
IV. In this course, basically, we will use just two kinds of logic: deductive and inductive.
A. Deductive Logic: concerned with determining when an argument is valid (i.e., deals with conclusive inferences).
1. A deductive argument is one which claims that its conclusion follows with necessity.
2. If that claim is not met, then the argument is said to be invalid.
3. Consider this example from Time magazine about the Kennedy assassination:
"Since tests proved that it took at least 2.3 seconds to operate the bolt on Oswald's rifle, Oswald obviously could not have fired three times--hitting Kennedy twice and Conally once--in 5.6 second or less."

2.3 The first load ned not be counted.
2.3 verses 2.3
+ 2.3 + 2.3
6.9 sec. 4.6 sec.
The response by Frederick T. Wehr: "Sir…This argument, which has appeared in many publications since

Get Access
Related
Get Access