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.While some athletes said committing early gave them a sense of relief 14and allowed them to put the recruiting process largely behind them, otherssaid it placed them in the difficult position of having to make significant deci-sions far earlier than they would have liked, and often with little time to thinkthe terms over. It s hard to know what you re going to want in a school and make such a 15huge life choice when you re 16, said one athlete.Did you make an early verbal commitment During what yearto play at your current school before the of high school didsport s official signing date? you verbally commit?71%JuniorYes 35%Senior63%Sophomore29% 2%NoEarly CommitmentsUsing Logical ReasoningThe structure of most texts used in research consists of a logical progressionof general points that lead to an overall thesis or conclusion; each point may be fol-lowed by more concrete statements of supporting evidence.The sequence ofgeneral points is determined by logical reasoning.For instance, if you look outa window and observe that the street and sidewalk are wet and the sky is over-cast, you would most likely conclude that it had rained recently.You didn t di-rectly observe the rain, but you can infer from past experiences with the sameevidence and apply this inference to a specific experience in the present.Al-though this may seem like a simpleminded illustration, it is typical of the rea-soning we all engage in every day.Or, to build on the preceding discussion of implication and inference (seepp.49 51): USING LOGICAL REASONING 571.Observers typically note that young boys display more physical energyin the classroom than girls do.(statement)2.They are restless and find it difficult to settle down to a task.(statement)3.As a result, many perform poorly in the classroom.(inference)4.To make it easier for boys to learn, we propose that short periods ofphysical activity be included in the daily schedule.(conclusion)There are two types of reasoning in formal logic deductive reasoning andinductive reasoning, each a distinct process for arriving at defensible conclusionsbased on evidence.Deductive ReasoningDeduction means reasoning from general statements to form a logicalconclusion.The classic format for deductive reasoning is the syllogism, which consistsof a series of carefully limited statements, or premises, pursued to a circum-scribed conclusion:All reptiles are cold-blooded.(premise)Iguanas are reptiles.(premise)Therefore, iguanas are cold-blooded.(conclusion)This is a line of reasoning based on classification, that is, the creation of ageneralized category based on shared traits.Members of the group we call reptiles have cold-bloodedness in common in fact, cold-bloodedness is adefining trait of reptiles.Iguanas are members of the group reptiles, whichmeans that they must also have that shared trait.Notice that the opening premise of a syllogism is usually a statement thatthe reader will be willing to grant as true without explicit proof.For example,each of the first two paragraphs of Steven Pinker s The Blank Slate (p.10) beginswith a (presumably) shared premise:1.Evolution has no conscience.2.Many creatures cooperate, nurture, and make peace.In each case, Pinker follows his major premise with a secondary premise and aconclusion:1.Evolution has no conscience, and (major premise)2.If one creature hurts another to benefit itself.(minor premise)3.Its descendants will come to predominate.(conclusion) 58 1 / READING FOR UNDERSTANDING1.Many creatures cooperate, nurture, and make peace.(major premise)2.[Human] genes are tied up in the same package, their children, so whatis good for one is good for the other.(minor premise)3.Humans in particular find comfort and joy in their families, friends, andcommunities.(conclusion)Deductive reasoning follows an almost mathematical rigor; provided thepremises are accepted as true and the line of reasoning valid, the conclu-sion must necessarily be true.Inductive ReasoningInduction means reasoning from specific evidence to form a generalconclusion.The conclusions reached through inductive reasoning are always condi-tional to some extent that is, there s always the possibility that some new ev-idence may be introduced to suggest a different conclusion.Given the availableevidence, you may be perfectly justified in concluding that a wet street and anovercast sky always mean that it has rained; but suppose one day, observingthese conditions, you turn on the radio and learn that a water main in the areahas broken overnight.That overcast sky may be coincidental, and you shouldbe prepared to revise your original conclusion based on the new information.Inductive reasoning uses the available evidence to construct the mostlikely conclusion.Using Logic to Establish Common Ground with the ReaderWhether authors support their theses by explanation, interpretation, orpersuasion or all three most of them use elements of inductive and deduc-tive reasoning to prove their claims.The reader is encouraged to re-create theauthor s logic and view an issue as the author does.The core of the reasoning isusually deductive, consisting of a series of premises or assumptions that the readershares or can be persuaded to share with the author.These premises oftendepend on common cultural values.That is why a thesis can lose its force overtime as values change.One hundred years ago, authors could safely reasonfrom the premise that heroism is defined by slaying the enemy in battle, or thatengaging in sex before marriage warrants a girl s expulsion from polite society,or that whipping young children is an effective and acceptable punishment.To-day, those statements would not have such wide credibility.In the same way,those readers who reject the concept of evolution will be indifferent to Pinker s USING LOGICAL REASONING 59premise that evolution has a conscience as well as the subsequent statementsthat follow from that initial assumption.To establish common ground with the reader, the author usually needs tospell out his or her assumptions and define them so precisely that they seemnot only true but inevitable.For instance, few people would challenge a claimthat cruelty to animals is wrong, but there is a wide range of opinion regardingexactly what constitutes cruelty, or whether certain specific activities (the use ofanimals in scientific research, for instance) are or are not cruel.If inflicting painserves some larger purpose, is it still cruel, or does cruelty refer only to un-necessary or unjustifiable pain? Before contesting the ethics of medical researchpractices, the author would have to begin by establishing a premise in thiscase, a definition of cruelty that the reader will also find acceptable [ Pobierz całość w formacie PDF ]