20(3)pp55-86TeachingSupplement3.pdf Flow Charts for Critical Thinking DANIEL E. FLAGE James Madison Un ive rsity Department of Philosophy and Rel ig ion Harrisonburg. Vi rginia 22807 Tel: 540-568-6394 E-mai l: flagede@jmu.edu TS 57 T hose of us who approach cri tica l thi nking as a thinly vei led course in informal logic are concerned with issues such as the strength of arguments (understood in terms of truth-preserving or truth-indicati ng re lations), the adequacy of explana- tions, and th e truth or probable truth (correspondence to the wo rld) of statements . If our goal is to empower st udents w ith a set of skills that will allow them to evaluate any piece of discourse , I believe this goal can be ac hieved if students ask a series of questions. What follows is a set of flowcharts that will walk a student through this evaluat ion process. I believe thi s might be a useful tool in our several approaches (e.g., informal logic, rhetoric) to teaching criti ca l thinking. I conside r the arrangement of the charts fai rl y natural. Insofar as we are fun- damentally concerned wit h the evaluat ion of arguments, it is reaso nable to begin with questions regarding arguments . T he early questions are very ge neral, fO l- lowed by more specific questions regardi ng deductive and inductive arguments, fOll owed by q ue st ions regarding the truth or falsehood of the premises. Answers to some questions direct students to oth er charts. Of course, in some circum- stances, students mig ht want to use some of the later charts indepe nden tl y . For example , if one's concern is whether to accept Professor Sm ith' s testimony re- garding eve nts in the American Revolution , one might want to go directly to the questions concerning testim ony in C hart #5. A flowchart approach to critical thinking is, by its natu re, quite ri gid: it is a hi gh ly structured dec isio n-procedure. Each ques tion is answered affirmatively or negatively. A nswers lead eit her to evaluative concl usions or to additional ques- ti ons. (n pri ncip le thi s shou ld result in uniform eva luations of arguments. In prac- tice, of cou rse: not ali stude nts will g ive the same answers to eac h of the ques- tions. And some questions-questions regarding what constitutes a "significant number" of shortcomi ngs in an inducti ve argument, for example-are questions for whi ch there often is no obviously correct answer. So, students should be prepared to defend their answe rs to the questions. While the evaluative structure is rigid , in practice there is ample room for reasoned dsagreement. The flowcharts provid e a st ructured summary of issues discussed in a critical thinking course. While I should like to say that the flowcharts account for at least some of the improvement my students exemplify by the end of the co urse, I have © biformaLLogic, 20.3 (2000) Tea ching Supp/emet//#3: pp. TS 57-TS 69. TS 58 Daniel S. Flage been unable 10 find a testing procedure 10 delennine Ihal the charts themselves account for the improvement. I hope you will find Ihe flowcharts useful. Charl/H Preliminary Questions Assuming there is an argument: I What arc the premises and conclusion?.-____ ______________ ., 2 Are ,there any ambiguilie·<,--".~ y,<,---... See Ambiguities. Chart #2 in the "gumr:o. J Are Ihe premises relevant __ ...... No, or don', know_ ...... See Relevance, Chart #) to the conclusion? 1 Yes. 4 Do the premises presume --...,.~ Yes, o r do n't know:. See Presumption, Chart #4 more than T ~:OUld? 5 Are any premises --...,.~ Yes. --...,~~ 6 What is (are) the prcmise(s)? left unstated? 1 No 71s the argumen .... Yes....,.. 8 Is it valid?' __ ~ ... NO. ___ •• What fallacy does deductive? I it commit? + Yes. No. 9 AIe the premises+ No.--- .... Unsound argument true ? ____ J . ----.. Yesb. --"". Sound argument Don't know. See bsct'.'allOn , Testimony, and Surveys. Chart #5 10 Jhat ,vid,nce ("sum,n!) ;,;...,. __________ -.1 there for the truth of the premises? Flow Charts (or Critical Thinking TS 59 .t TIll! argument is inductive, I I Doesa P±nlise make an-'ye4 12 1sthe authoti ty -+ Don't know. -..see Chan #5 NO.----i •• The suppo rt ana logy? 1 is w,,",,n,d. 25 Are there differences Ihal J,rt!nglil t.'17 the---~.' No. ---~.' The support an:llogy? is weake ned. 1 Yes. 26 Is the conclusLon Strong re lal ive 10 ____ •• Yes. ----t •• The su ppo rt 10(' pr<:'mises? is weakened. I No. 27 Arc the remlses ----t •• No.---~ •• The support lTue? 1 is weakened. Yes . 28 What (,,,jdence (argum('nI) is there fo r Ihe Irulh::. __________________________ --' . h .,' 01 I t! premIses. 1 29 Are Iherl! a "sig niJicant number'c' __ ~ •• Y"~ ___ •• The suppOrt is o feknlellts that WEAK : e.'ipktin lend 10 w('aken the why. stl ppon? 1 The sUPpO rt is STRONG. No. , In some cases, by an s ..... ermg the prevIOus qU(slions yOu have cX3mincd [he cvid-. Is the claim true?--;,. No.+ The Olrgumcnt true of a whole or an commits the entire class o f objects and fallacy o f the conclus ion a claim Yes division and th il t ascribes the same should be property to o ne of the parts or a mcmberofa class? I No. E· hit b· · · ~ 11 er t left! ]S no am IgULly In the argument, or the persuasive force of the argument does not rest on that amb igu ity. Return to Chart I, Question ) . rejected. Does the premise aplXa l lo Flow Charts for Critical Thinking Chart #3 R elevance some undesi rabl<' __ -:--:-_ _ ~ •• Yes. --____ II Thc argument com m its tht: conseque nce if thl! co nc lu s ion fa llacy of appeal 10 fo rce and is not acce pted as true ? sho uld be rejected. ~ No TS 63 Does the prem ise co nsist of an----' Yes. --____ II< The argument commi ts the fallac y anack On a ll individual rathe r than a of personal atlack and should be criticism of hi s o r her position? rejected. ~ No Is a premise Ih li lhe propone nt's-. Ye s. ______ II The argument is a person al aHack ac tio ns are inco ns istent with (III quolJlle) and sho ul d be hi s or her words? rejected. ~ No Docs a premise appea l 10 Ihc·--..... Yes. ---.. Does Ihe pe rso n still hold th e incon~istcllcy in somconc's position? po,; I; on? I No. No. The prem ise is irrelevant. Reject th e argumenL \es The premise is re le va n!. Return to Chan. I , Question 4. Does a pre mise appea l to a _ _ -.~ Yes. __ -.~ The argument in volves mob dt!sirt! to be loved or appea l and should be rejected. spec ial ? 1- No. Does a pre mise appc!'al to dire ----.. Yes. ---'IJ T his is an ap peal 10 pity and circ um stance s to get a should be rejected. conclusion accepled? ~ No Does 1l prem ise appeal 10 a .. Yes. T he argume nt comm it s the fallacy of general rule in ci rcu mstan ces ---. .. acc ide nt and shou ld be rejected. in which the rul e does not apply? • TS 64 Daniel S. Flage 1 No Does a premise distort ____ ~ •• Yes. __ --. .. This is a siraw person fallacy . The someone's position? premise is irrelevant, and the Does a premise shift away from the issue under consider;Jlion? argument should be rejected. ----. .. Yes. --~.. This is a red herring . The premi se is irrelevant, ami the argument sho uld be rejecte d. Do Ihe J\i,,~:ppcar 10 ___ .~ Y CS. ___ .~ This is an irre levan t conclusion and support one conclusion bUI the argument should be rejected. another is ldrawn? No. Is there some other way in .. Yes. --~.~ Explain Ihe: irrekva nce a s a which the truth of Ihe premises rea son to reject the arguml.!nL does n Ol increase by the slightest amount the probability \1l:11 the conclusion is true? 1 No The prcmisl.!s appem to bt: "Icvam 10 tc conclusion. Return 10 Chart I. Question 4. Flow Charts fo r Critical Thinking C h:.ari U rn:su mpt io ll TS 65 Do.:s one orlhc premises ___ .~ Yes. __ -.. nl<:: argumcnt bc=gs the quest ion restate Ihe conclusion? and should be rejected. Is there a serie-s ofargumcms,--". Yes. .. The argument begs the qucsl ion in which the conclusion of the and shou ld be rejected. I." is , pre'r::r ' he "rst? Is the argument based on a __ -. ... Yes. ... Is the presumed answer reasonable? ques tion lhnt assumes a (NO \Y'< previous question has been ... .. answered? 1 Complex question: Return to Chart I, No. Reject the arl;ument. Question 5. '·Ias evidence which is COntrary ----t •• ycs~. ---t •• Supprcssi,."d ev idence: to the COllcll1lSi:obecn ignored? ~~~:~~~~~~;i!~~:~tnl' Question S. Does a disjunctive premise leave ---~Jo Yes. ---t •• False dichotomy; rejcci the oul possibilities? ilr~ument. 1 No Are there other ullwarrilnted ----.--,~~ Yes. ---. .. Explain why the argument presupposi tions"? should be rej ected . There appear to be no ullwarranted assumption s. 1 Return to Chart 1, Question 5. TS 66 Daniel S. Flage Char t #S Observatio n, Tes timo n y, a nd Surveys Test imony comes in many forms . There art: observation claims-and the processes of observation- which require evaluation. There are authoritative testimonies. There an: surveys. In each case, to evaluate the claims made you, ill effect, engage in inductive reasoning. The questions on these charts provide a guide for evaluating claims of each son. Like a ll cases of inductive reasoning, however. answering these questions will nul provide conclusive reasons for your evaluation. Obse rva lio n Was the observer physically in -----I •• No.---~ •• Is there a way 10 explain how a position to make the observation? The observa tion could have been made. e.g., surveillance cameras? Yes. Were the observation conditions adequate? Yes. No. There is insufficient evidence to accept the observation claim. ---.~ No iii Support for the claim is weakened. Iyes Was some tecinOIOgiCal device __ ~.~ Yes. .. Did the observer use that needed 10 make thl! observation? /nOI*giCal de .... ice? Yes. No. No. " Did the observe r know Support for the how to use that de .... ice? /~ Yes . observation claim is weakened. " . upport fo r the observallon claim is weakened. Does !he ob",,,, ha" !h~ • !uppon for the obsc No ---•• S upport for the claim is he 0 ' she is F:? we,kened, Is the claim consiste nt with .. No. .. Suppo rt for the claim is oth" thin gs you know? ~ weakened, Is the persoli:::~ Y- y,,- RejcC1the conclusion. conclusion been sig nificantly weakened? l No Accept the conclusion. Return to Chart 1, Question 17,1 ! I wish to thank Claude Gratlon (or his vcry helpful ct)mmen15 on an earliu version of th is papa TS 69