Reading Exercise: Converses and Contrapositives on Propositions

Name
Affiliation
Course
Professor
Date
Topic 5 Reading Exercises
Copi, Irving M. Introduction to Logic, 14th Edition. Routledge.
EXERCISE A INSTRUCTIONS
State the converses of the following propositions, and indicate which of them are equivalent to the given propositions:
PROBLEMS
1. No people who are considerate of others are reckless drivers who pay no attention to traffic regulations.
Equivalent
No considerate reckless drivers are considerate of others.
2. All graduates of West Point are commissioned officers in the U.S. Army.
Non-equivalent
Some commissioned officers are graduates
3. Some European cars are overpriced and underpowered automobiles.
Equivalent
Some overpriced and underpowered automobiles are European cars
4. No reptiles are warm-blooded animals.
Equivalent
No warm-blooded animals are reptiles
5. Some professional wrestlers are elderly persons who are incapable of doing an honest day’s work.
Non-equivalent
some elderly women are professional wrestlers
EXERCISE B INSTRUCTIONS
State the obverses of the following propositions:
PROBLEMS
1.Some college athletes are professionals.
Are non-professionals
2.No organic compounds are metals.
Are non-metals
3. Some clergy are not abstainers.
Are non-abstainers
4.No geniuses are conformists.
Are non-conformists
5. All objects suitable for boat anchors are objects that weigh at least fifteen pounds.
Are non-objects that weigh at least fifteen pounds
EXERCISE C INSTRUCTIONS
State the contrapositives of the following propositions and indicate which of them are equivalent to the given propositions.
PROBLEMS
1. All journalists are pessimists.
Equivalent
All pessimists are journalists
2. Some soldiers are not officers.
Equivalent
Some non-officers are non-soldiers
3. All scholars are nondegenerates.
Equivalent
All degenerates are non-scholars
4. All things weighing less than fifty pounds are objects not more than four feet high.
Non Equivalent
All things less than fifty pounds are not the same than four feets high
5. Some noncitizens are not nonresidents.
Equivalent
Some residents are not citizens.
EXERCISE D INSTRUCTIONS
If “All socialists are pacifists” is true, what may be inferred about the truth or falsehood of the following propositions? That is, which can be known to be true, which can be known to be false, and which are undetermined?
PROBLEMS
1. Some nonpacifists are not nonsocialists.
True
2. No socialists are nonpacifists.
True
3. All nonsocialists are nonpacifists.
True
4. No nonpacifists are socialists.
false
5. No nonsocialists are nonpacifists.
false
6. All nonpacifists are nonsocialists.
True
7. No pacifists are nonsocialis...