C1 The tuna population will vanish unless the tuna industry is regulated more stringently
This is easier to read, and it saves you having to write things out unnecessarily. Henceforth, whenever an argument draws an inference from a conditional premise, feel free to abbreviate in this way. CHAPTER This chapter was concerned to address some of the main logical SUMMARY problems encountered in the reconstruction of arguments. In many cases, one or more premises upon which a conclusion depends is left implicit by the arguer. A necessary part of reconstruction is to make such premises...
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Once we put the two steps of the argument together to form a complex argument, we see that it begs the question of who should get the biggest share P1) I'm getting the biggest share of the haul. P2) Whoever receives the biggest share of the haul is the leader. C1) I must be the leader of the gang. P3) Gang leaders always receive the biggest share of their gang's haul. C2) I'm getting the biggest share of the haul. Thief number one is guilty of begging the question (in addition to armed robbery)...
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Those days, people didn't succumb to anorexia or bulimia and the incidence of obesity was much lower. Seems the 'experts' have got it wrong again. This argument seems to conclude not only that eating traditional British cooking protects people from anorexia, bulimia and obesity, but that not eating it causes those things. To expose the fallacies, we can reconstruct the entire argument as an extended argument P1) When we ate traditional foods (X) there was a significantly lower incidence of...
Faris
Rhetoric - Any verbal or written attempt to persuade someone to believe, desire or do something that does not attempt to give good reasons for the belief, desire or action, but attempts to motivate that belief, desire or action solely through the power of the words used. The difference between fallacies and rhetorical ploys is understood most easily as a difference in the function of the language being employed. As we saw in Chapter 1, politicians, advertisers and newspaper columnists tend to...
Probability
We express the probability that a given proposition is true (or that a given event has occurred or will occur) on a numerical scale between 0 and 1, expressed either as a decimal or as a fraction. For example the probability that a tossed coin will land heads-up is 0.5 or 1 2. Perhaps surprisingly, there are different ways in which to explain probability. We'll briefly consider three proportion, frequency, and rational expectation.1 First, proportion. Many arguments contain a premise that says...
Radiant Thinking For A Single Person
Of decriminalisation can use it in support of their cause their opponents can use it to back up their anti-decriminalisation stance (the latter might say, 'Only some members of parliament support. . .'). 3 Often people simply omit quantifiers. For instance, someone might protest Lecturers don't give students a chance to complain. At face value this might appear to convey the proposition that No lecturer (ever) gives a student a chance to complain. Yet it is likely that what the speaker really...
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Is clearly not an inductively forceful argument. If the only propositions you knew relevant to the conclusion were PI and P2, then you would be wrong to think that C is probably true. To say that all rodents have tails is the same as saying 'Every rodent has a tail', or 'Any rodent has a tail', or 'No rodent has no tail'. To say that most rodents have tails is to say that more than half of all rodents have tails, or that there are more rodents with tails than there are without them. But what...
Covering generalisations
In the politician case, the connecting premise was a generalisation (review the discussion of generalisations in Chapter 1 if you are not clear about what a generalisation is). Connecting premises are usually generalisations. But in the inflation case the connecting premise we used was a conditional (see Chapter 2). This is also common. However, there is an important relationship between conditionals and generalisations that must be appreciated. Consider the following propositions (a) If Betty...
Scorpios tend to be luckier than Libras
John does not believe in astrology, and therefore does not believe that one's fortune depends on the part of the year during which one is born. So he thinks this proposition is false. But John, wishing to avoid a painful disagreement, expresses himself by saying, 'Well, that may be true for you, but it isn't true for me'. As we have just seen, where implicit speaker-relativity is involved, the use of such phrases as 'true for you' is perfectly legitimate. But in the astrology case, the use of...
Abortion is immoral
According to the relativist view, when anti-abortionists say abortion is morally unacceptable and their opponents contradict them and say that it is morally acceptable, there is no real disagreement rather the two sides do not share the same moral preferences. Thus, for the relativist, value-statements are always speaker-relative, whether implicitly or explicitly. An apparent disagreement over a value is in this respect like that between Julie and John concerning chocolate versus vanilla ice...
Argument commentary
We have now completed our survey of our basic concepts and procedures of argument analysis. By 'argument analysis' we mean a two-stage process comprising first the reconstruction, then the assessment of the argument. At this point, we need to say a bit more about the final product of this process. When the analysis of an argument is undertaken, you may sometimes want to produce a piece of written work which summarises the analysis you have made. This should consist of three parts 1 The argument...
The scope of a generalisation
Consider the following hard generalisations 2 All black cows are herbivores. The subjects of these generalisations - what the generalisations are about - are cows and black cows, respectively. Both generalisations are true, and they stand in a special relationship. There are two aspects of this relationship. First, they attribute the same feature to their subjects (that of being herbivores). Second, the subject of the second is a subset of the first (all black cows are cows). Thus we say that...
Chocolate ice cream tastes better than vanilla
The implicit speaker-relativity of a sentence like this might be described by saying that the sentence is true for Julie, and not true for John. Upon hearing Julie assert this sentence, John might say, 'Well, that may be true for you, but it isn't true for me'. John might, in this case, simply be making the point about implicit speaker-relativity. If so, then that is all right he is quite right to do so. However, phrases such as 'true for me' are sometimes used in what appear to be factual...
2Vanilla ice cream tastes better than chocolate to John
These are two different propositions. There is certainly no logical conflict between them they could both be true. But in that case, Julie and John 2 There is one slight complication, however statements of this kind may mean that something is preferred or liked by most people. For example, this is plausibly what someone means who says 'Soured milk does not taste good'. Nevertheless, these statements are still implicitly relative, because they still depend for their truth on reference to...
More on generalisations
As we noted in Chapter 1, only hard generalisations can rightly be conveyed by using a quantifier-word like 'all', 'no', or 'every'. Indeed, that is the usual function of those words - to make it perfectly explicit that a hard generalisation is what is intended. For example someone at a meeting of Parliament might say, 'Every single MP in this chamber takes bribes', rather than 'The MPs in this chamber take bribes'. Soft generalisations, indeed, are very often expressed without any quantifier...
C1
In this case the argument whose conclusion is CI is a sub-argument for an extended argument whose conclusion is C2. You would first assess the argument from PI and P2 to CI you would then assess the argument from CI and P3 to C2. Finally, you would use these results to assess the total argument from PI, P2 and P3 to C2. Assessment is to be distinguished from reconstruction, which is discussed in more detail in the next chapter. Broadly speaking, assessment may be said to fall into two...
Implicit and explicit
Not only do actual statements of arguments typically include a lot of material that is inessential to the argument, they often exclude some of what is essential to the argument some essential propositions are left implicit, when our task in reconstruction is to make the argument fully explicit. To say that a proposition is implicit in an argument is to say that it is part of the argument intended by the arguer - either as a premise or as the conclusion - but that it has not actually been stated...
Extraneous material
The first step in analysing and reconstructing an argument is to identify its conclusion, then its premises. But much of what people say or write, when advancing an argument, plays no argumentative role. Much is there for emphasis, or is rhetorical, or plays some other role than that of expressing the propositions that properly constitute the argument. When reconstructing arguments, then, we have to hive off this extraneous material. Here's an example we've given each sentence a number in order...
Info
Negation of its antecedent not P for the conclusion that the consequent is also negated not Q . The invalidity of this pattern can be seen clearly using a version of the example above P1 If mortgage rates go up P , house prices will fall Q . P2 Mortgage rates have not gone up not P . C House prices will not fall not Q . The invalidity here has similar grounds to that of the fallacy of affirming the consequent. There are conditions other than mortgage rates going up that could precipitate a fall...
Whenever The Cherry Trees Blossom The Weather Begins To Get Warmer
Democracy is the best system of government. Most people in the world believe in the superiority of democratic systems. Fallacy of majority belief P1 Most people believe in democratic systems. P2 Any belief held by the majority is true. C Democracy is the best system of government. a Our lecturers are always extolling the virtues of critical thinking, but they would say that wouldn't they They only keep their jobs if they've got students to teach. b It's not illegal for me to exaggerate my...
Iiiit is not an inductively forceful argument that is defeated for that person
It can even happen that an argument is rationally persuasive for you at one time, but not at a later time, because you have acquired new evidence which defeats the argument by suggesting that the conclusion is false, more strongly than the argument suggests its truth . To be strictly accurate, then, we should speak of rational persuasiveness for a person at a particular time. For the sake of simplicity, however, we have omitted this complication from what is already a rather complex definition....
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And so on, they invite pop stars to their parties and comport themselves as if they too were pop stars, just out to sell themselves really. In this example the speaker gets side-tracked into commenting upon the prime minister's suits and party guest-lists, and fails, beyond the vague charge that the government's policies are 'poll-driven nonsense', to offer a substantive criticism. Most of what is said is at best only obliquely relevant to the issue. 4 As with conclusions, there are certain...
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The focus of this book is written and spoken ways of persuading us to do things and to believe things. Every day we are bombarded with messages apparently telling us what to do or not to do, what to believe or not to believe buy this soft drink eat that breakfast cereal vote for Mrs Bloggs practise safe sex don't drink and drive don't use drugs boycott goods from a particular country abortion is murder meat is murder aliens have visited the earth the economy is sound capitalism is just...
