Lesson ThreeInformal Logic

By the end of this lesson, you should know:

How to use informal logic to effectively organize an argumentative essay.

Today’s Objective

“The aim or purpose of argument is to use logic (both inductive and deductive) to

create reasoned communication of ideas, insights, and experiences to some audience

so as to produce a new understanding of some issue for that audience.”

argument

Analytical Thesis StatementA thesis statement that analyzes the

relationship among various significant ideas contained in the thesis sentence(s)

Thesis Statements

Structure of Analytical Thesis StatementsThis pattern can serve as an aid:

Independent clause(s) + restricting clause(s) [general ideas are stated] [qualifying idea(s) defined]

Thesis Statements

Outlining

“A thesis statement focuses both the writer’s and reader’s attention on specific issues to be

developed within an essay.”

In addition, analytical thesis statements analyze the relationship among these significant ideas.

If you have a good analytical thesis statement, creating an outline is relatively easy.

Outlining

There are essentially two major ways to draft an outline from a thesis statement:

1. Isolating key ideas to be developed

2. Using informal logic

Outlining

Outlining

From Thesis Statement to OutlineExample:

“University education is more beneficial than technical training [independent / generalization] because at the university the students have the opportunity to learn technical and career related skills as well as to acquire perspectives on life from studying subjects like philosophy, art, and literature [restricting idea].”

From Thesis Statement to OutlineExample:

We immediately recognize that the driving organizational force behind the thesis statement is

comparison & contrast.

At the most general level, we are comparing & contrasting university education to technical

training.

Outlining

From Thesis Statement to OutlineExample:

The restricting idea helps us focus the general comparison to two major focus points:

1. Opportunities to learn2. Perspectives on life

Outlining

From Thesis Statement to OutlineNow, let’s create an outline from these key ideas.

As you know, with comparison & contrast there are two ways to organize our outline:

1. Subject by subject2. Point by point

Outlining

I. IntroductionII. University EducationIII. Technical TrainingIV. Conclusion

Outlining

I. IntroductionII. University Education

A. Opportunities to LearnB. Perspectives on Life

III. Technical TrainingA. Opportunities to LearnB. Perspectives on Life

IV. Conclusion

Subject-by-Subject

I. IntroductionII. Opportunities to Learn

A. University EducationB. Technical Training

III. Perspectives on LifeA. University EducationB. Technical Training

IV. Conclusion

Point-by-Point

From Thesis Statement to OutlineExample:

There is one more key idea that is implicit in the thesis statement (this would be easily recognizable

using informal logic):

“Acquiring perspectives on life in addition to technical and career related skills is more

beneficial than acquiring only technical and career related skills.”

Outlining

I. IntroductionII. Opportunities to Learn

A. University EducationB. Technical Training

III. Perspectives on LifeA. University EducationB. Technical Training

IV. Learning vs. PerspectivesV. Conclusion

Point-by-Point

From Thesis Statement to Outline

Now, let’s try to think through this a different way: by using informal logic.

Look at logic handouts.

Outlining

Outlining

Deductive conclusion

Inductive premise

From Thesis Statement to Outline

“University education is more beneficial than technical training [independent / generalization] because at the university the students have the opportunity to learn technical and career related skills as well as to acquire perspectives on life from studying subjects like philosophy, art, and literature [restricting idea].”

Syllogism:Inductive Premise 1: At the university the

students have the opportunity to learn technical and career related skills as well as to acquire perspectives on life from studying subjects like philosophy, art, and literature.

Premise 2: ?Deductive conclusion: University education is

more beneficial than technical training.

Outlining

From Thesis Statement to OutlineSyllogism:

Inductive Premise 2: Acquiring perspectives on life in addition to technical and career related skills is more beneficial than acquiring only technical and career related skills.

Outlining

From Thesis Statement to OutlineExample:

“Love is disappearing [independent / generalization] because individualism is the main survival technique in today’s fiercely competitive society [restricting idea].”

Outlining

From Thesis Statement to OutlineExample:

We immediately recognize that the driving organizational force behind the thesis statement is

cause & effect.

At the most general level, we are asserting that love is disappearing because of individualism.

Outlining

From Thesis Statement to Outline

Premise 1: ?Premise 2: Individualism is the main survival

technique in today’s fiercely competitive society. Conclusion: Love is disappearing.

Outlining

From Thesis Statement to Outline

Premise 1: Individualism and love are mutually exclusive.

Premise 2: Individualism is the main survival technique in today’s fiercely competitive society.

Conclusion: Love is disappearing.

Outlining

HomeworkUse key ideas and informal logic to create a syllogism / outline for your thesis statement.

Pg. 127 - 129

ReadingReview Informal Logic Handouts

There will be a vocabulary quiz next week.