Thinking Skills: Critical Thinking and Problem Solving

7.2 Soundness and validity: a taste of logic 255 reasons. The fact (R2) that birds have wings doesn’t mean all of them can fly, ...

256 Unit 7 Critical reasoning: Advanced Level resolve that dispute, [5] remains valid, as the Euler diagram confirms: have gills ...

7.2 Soundness and validity: a taste of logic 257 that express them. As we have seen, symbols, diagrams and formulas can be used ...

258 Unit 7 Critical reasoning: Advanced Level If p then q q p and [11]: If p then q Not-p Not-q These might seem minor differenc ...

7.2 Soundness and validity: a taste of logic 259 Commentary The answer is that the argument is not sound, but it is valid. Make ...

260 Unit 7 Critical reasoning: Advanced Level not support the conclusion. Even if we later find out that the conclusion was in f ...

7.2 Soundness and validity: a taste of logic 261 Summary • The soundness of an argument depends on two factors: (1) the truth ...

262 Unit 7 Critical reasoning: Advanced Level Consider the following simple demonstration. (You probably saw it at elementary sc ...

7.3 Non-deductive reasoning 263 because every swan that had ever been observed was white. That was until a species of black swan ...

264 Unit 7 Critical reasoning: Advanced Level a reason for arguing that it is true. Not surprisingly, reasoning of this kind is ...

7.3 Non-deductive reasoning 265 B and C are not cases of ABE. ABE proceeds from an observed fact to a hypothesis which would exp ...

266 Unit 7 Critical reasoning: Advanced Level objection to the argument that merely points out random differences has little val ...

7.3 Non-deductive reasoning 267 Commentary The first and perhaps most interesting analogy is the one that J makes when she is to ...

268 Unit 7 Critical reasoning: Advanced Level effectively breaking the rule that two wrongs do not make a right. It is also a fo ...

7.4 Reasoning with statistics 269 7.4 Reasoning with statistics so on. If someone said to you: ‘Prison works because it reduces ...

270 Unit 7 Critical reasoning: Advanced Level simply because they are not proportions: they are bald totals. If I supported my c ...

7.4 Reasoning with statistics 271 Commentary The first thing to do when faced with any statistical document is to clarify precis ...

272 Unit 7 Critical reasoning: Advanced Level need to know why the rate is higher in one country than another, whether there wer ...

7.4 Reasoning with statistics 273 Commentary Well, the facts (as presented in the graphs) may speak for themselves, but do they ...

274 Unit 7 Critical reasoning: Advanced Level lacking from the experiment is a second group in which prison sentences are reduce ...