CRITICAL POINTS Basic Critical Thinking Concepts

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CRITICAL POINTS Basic Critical Thinking
Concepts

• Essentials of Clear Thinking
• Propositions and Issues

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Notes on Propositions

• A proposition is a declarative sentence that is
  either true or false, though this cannot always
  be determined at any particular time.

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Notes on Propositions

• A proposition is a declarative sentence that is
  either true or false, though this cannot always
  be determined at any particular time.

Proposition Al Gore received a majority of the
popular vote in the 2000 election. Proposition
Unprotected sex will kill you. Proposition God
loves us. Not a proposition Got milk?
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Notes on Propositions

• A proposition is a declarative sentence that is
  either true or false, though this cannot always
  be determined at any particular time.
• Propositions that one would take as expressing
  judgments are either acceptable or not.

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Notes on Propositions

• A proposition is a declarative sentence that is
  either true or false, though this cannot always
  be determined at any particular time.
• Propositions that one would take as expressing
  judgments are either acceptable or not.

That color looks really good on you. One should
always tell the truth.
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Notes on Propositions

• A proposition is a declarative sentence that is
  either true or false, though this cannot always
  be determined at any particular time.
• Propositions that one would take as expressing
  judgments are either acceptable or not.
• Accepting a proposition means taking it as true.

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Notes on Propositions

• Rejecting a proposition and suspending judgment
  both evaluate logically to FALSE.
• The reason why a suspended judgment makes a
  proposition logically FALSE is because there is
  not enough support to justify accepting the
  proposition as TRUE.

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About propositions and issues...

• Issues arise when a proposition is in question.

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About propositions and issues...

• Issues arise when a proposition is in question.

I wonder if I should register to vote. The
question is whether enforcement of the noise
ordinance is fair.
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About propositions and issues...

• Issues arise when a proposition is in question.
• Two kinds of questions (1) What is the position
  being taken? (2) Is that position correct?
• The second question is whether a proposition
  should be accepted or rejected, or whether the
  most responsible position would be to suspend
  judgment.

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About propositions and issues...

• Key concept Arguments present reasons to decide
  an issue one way or another.
• Arguments only make sense if the meanings of
  claims are clear.
• Even after an argument has been presented, one
  can still suspend judgment about the
  acceptability (truth) of its conclusion.