An inconsistent triad is a set of three propositions that cannot all be true together. For example, 'She was an orphan; Tim outlived her; Tim was her father'.
All inconsistent triads lead to
trilemmas:
* If A and B are true, C must be false.
* If A and C are true, B must be false.
* If B and C are true, A must be false.
Epistemology
# Knowledge is justified true belief.
# Humans cannot provide justification for their beliefs.
# Humans possess knowledge.
Political philosophy
# A just society maximizes individual liberty.
# A just society maximizes material equality.
# A just society cannot maximize both liberty and equality.
Ethics
# Actions that maximize overall well-being are morally right.
# Lying can sometimes maximize overall well-being.
# Lying is always morally wrong.
See also
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Classical logic
Classical logic (or standard logic) or Frege–Russell logic is the intensively studied and most widely used class of deductive logic. Classical logic has had much influence on analytic philosophy.
Characteristics
Each logical system in this c ...
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Contradiction
In traditional logic, a contradiction involves a proposition conflicting either with itself or established fact. It is often used as a tool to detect disingenuous beliefs and bias. Illustrating a general tendency in applied logic, Aristotle's ...
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Dilemma
A dilemma () is a problem offering two possibilities, neither of which is unambiguously acceptable or preferable. The possibilities are termed the ''horns'' of the dilemma, a clichéd usage, but distinguishing the dilemma from other kinds of p ...
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Formal logic
Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the study of deductively valid inferences or logical truths. It examines how conclusions follow from premises based on the structure o ...
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Reductio ad absurdum
In logic, (Latin for "reduction to absurdity"), also known as (Latin for "argument to absurdity") or ''apagogical argument'', is the form of argument that attempts to establish a claim by showing that the opposite scenario would lead to absur ...
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Trilemma
References
Further reading
* Brewer, B. (2011). ''The Inconsistent Triad''
Perception, Causation, and Objectivity 68.
* Howard-Snyder, F., Howard-Snyder, D., & Wasserman, R. (2009).
The Power of Logic' (4th Edition). New York: McGraw-Hill. (p. 336) {{ISBN, 978-0-07-340737-1
Syllogistic fallacies