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The Elements of Argument. OCSA LCI. Key Terms. Claim : A statement that requires evidence to support it. Previously, you may have called this an opinion or a thesis. Ex: The federal government lends too much money to other nations.
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The Elements of Argument OCSA LCI
Key Terms • Claim: A statement that requires evidence to support it. Previously, you may have called this an opinion or a thesis. • Ex: The federal government lends too much money to other nations. • Premise: A statement or reason offered as support for a claim • Ex: America is in the worse economic crisis since the 1920’s. • Ex: Money that goes to other countries will not go towards our country’s problems: education, social security, medicare, etc. • Conclusion: The claim being supported by a premise or premises • Therefore, we need to stop lending money to other countries and take care of our own fiscal problems.
Key Terms • Argument: A conclusion together with the premises that support it • Reasoning: The process by which one derives a conclusion from a set of premises. This is either OR • Valid: an argument whose premises genuinely support its conclusion • Unsound: an argument that has at least one false premise [an untrue statement]
What did she just say? Inductive Deductive Premises (statements, reasons) Reasoning Conclusion (opinion, thesis) Unsound/ invalid Argument Sound/valid Deductive - facts - generally accepted truths Inductive -inferences - observations
Let’s look at the examples from the gallery walk • Mikhail hails from Russia and all Russians are tall, therefore Mikhail is tall. • Inductive - because the premises are observations. • REASONING valid but not SOUND: not all Russians are tall. It is not the only conclusion possible and needs more evidence.
#2 • When chimpanzees are exposed to rage, they tend to become violent. Humans are similar to chimpanzees, and therefore they tend to get violent when exposed to rage. • INDUCTIVE both premises are observations • REASONING depends on whether you accept the premise that humans are similar to chimpanzees…regardless, this needs more evidence to make the conclusion concrete.
#3 • All men are mortal. Socrates is a man, and therefore he is mortal. • DEDUCTIVE all facts • REASONING valid
#4 • The woman in the neighboring apartment has a shrill voice. I can hear a shrill voice from outside, therefore the woman in the neighboring apartment is shouting. • INDUCTIVE because the premises are observations and the conclusion is not concrete. • REASONING IT IS SOUND because it is possible but we need more evidence that the sound is from the neigboringwoman!
#5 • All the tigers observed in a particular region have yellow black stripes, therefore all the tigers native to this region have yellow stripes. • INDUCTIVE because it is based on observations • REASONING VALID But! We need more evidence. We need to observe ALL the tigers. And we need proof that these tigers are natives!
#6 • All oranges are fruitsAll fruits grow on treesTherefore, all oranges grow on trees • DEDUCTIVE • REASONING INVALID because the second premise is FALSE!! Therefore, the entire argument is false.
#7 • All bachelors are singleJohnny is single,Hence, Johnny is a bachelor • DEDUCTIVE because the premises are FACTS and the conclusion is concrete. • REASONING VALID because if the premises are true, then the conclusion is valid.
Two Traditional Means of Approaching the Thesis deductive reasoning • the thesis appears toward the beginning of the text, then specific details follow in the body of the essay that support this point inductive reasoning • the reader/writer first develops the importance of the point s/he wishes to make, THEN synthesize multiple points to infer a GENERAL thesis
Two Traditional Means of Approaching the Thesis deductive reasoning • commonly associated with “formal logic.” • involves reasoning from known premises, or premises presumed to be true, to a certain conclusion. • the conclusions reached are certain, inevitable, inescapable. inductive reasoning • commonly known as “informal logic,” or “everyday argument” • involves drawing uncertain inferences, based on probable reasoning. • the conclusions reached are probable, reasonable, plausible, believable.
Two Traditional Means of Approaching the Thesis deductive reasoning • Deductive reasoning is either “valid” or “invalid.” A deductive argument can’t be “sort of” valid. • If the reasoning employed in an argument is valid and the argument’s premises are true, then the argument is said to be sound. inductive reasoning • Inductive reasoning enjoys a wide range of probability; it can be plausible, possible, reasonable, credible, etc. • the inferences drawn may be placed on a continuum ranging from cogent at one end to fallacious at the other.
Two Traditional Means of Approaching the Thesis valid reasoning + true premises = sound argument fallacious <---------cogent