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Rigorous Reasoning

Peter Cave spots a few fallacies.

Reasoning is pervasive, but rigour is resisted; rigour is rare.

A mother, according to a recent Independent on Sunday report, sought to reject her daughter’s animal rights concerns by referring to the natural and widespread character of meat-eating, the implication being that meat-eating is not wrong because it is so widespread and natural. Although other issues arise – what we understand by ‘natural’, whether a newspaper extract provides a fair summary of the discussion – the present purpose is one of illustration, the illustration of poor reasoning and of the need for good.

If someone seeks to defend rape or unfair discrimination or earthquakes – or even the common cold – by saying that such things have always been around and are ‘perfectly natural’, we should be unimpressed. Just because suffering and injustice are natural and widespread it does not follow that it is wrong to oppose them. This may strike us as obvious, but it only becomes obvious for some people once it is spelt out. The mother above is just one instance of someone sincerely arguing for a conclusion, yet unwittingly making a simple mistake.

If we value getting things right, then we need to be concerned about the means whereby we reach our conclusions; we need to spot mistakes. While there is today a public airing of the deficiencies in educational standards – for example, school-leavers’ ignorance of Shakespeare – there is little said about standards of reasoning in general. Much is spoken of poor spelling and the inability to multiply without use of a calculator; much criticism is voiced of (allegedly) declining moral standards of young people. Little is said of the lack of rigour in argument.

A cynic might suggest that the paucity of concern for reasoning rigours results from selfinterest. Some in authority and positions of influence, be they government ministers or newspaper editors, know that the more people are aware of reasoning standards, the more likely they are to adopt a critical stance towards encountered reasoning. If people could more readily spot mistakes in reasoning – and recognise the value of so doing – questions would be raised about many claims by those in public life as well as those in a public house.

When philosophers examine a piece of reasoning to see whether it is any good, they will often talk about whether the argument is logically valid; and although philosophers disagree about many issues, there is general consent regarding the validity of many different argument forms. The reference to ‘argument’ is not, of course, a reference to what may go on outside a public house at closing time. An argument is produced when someone makes a claim and gives reasons for that claim; a sequence of steps may take us to the conclusion of the argument from the stated reasons or premises of the argument. A central question is whether or not the conclusion logically follows from the premises. A test for this is to ask whether the premises could be true and the conclusion false. If this is possible, then the conclusion does not follow from the premises – and we have a deductively invalid argument, a bad argument, a non sequitur. Here we have engaged logic, logic being the science of valid argument.

In the example cited at the beginning, the argument might have been baldly presented with the premise that meat-eating is natural and the conclusion that meat-eating is not morally wrong. The argument is invalid because the conclusion does not follow from the premise.

The argument could have been made a little complicated so that it ran with the premises that (1) if something is natural, then it is not morally wrong and (2) meat-eating is natural. The conclusion drawn could then be that (3) meateating is not morally wrong. This is a valid argument with the conclusion following from the premises; but now we may challenge the first premise. Is it true that if something is natural then it is not morally wrong? It would seem not.

The challenge to a piece of reasoning is a challenge concerning consistency. If someone really does stand by the argument and the premises in the previous paragraph, then – in order to be consistent – she or he would have to accept that because violent acts occur naturally, they too are not morally wrong.

Some might take the brave path of claiming that there is no non-relative right or wrong in the assessment of any reasoning, no non-relative truth or falsity; what is right for you could be wrong for me. Such a relativist claim itself is true or false – or is it just true for the relativist?

Not all reasoning involves a conclusion being presented as logically following from the premises. Rather, some evidence might be given to suggest that a conclusion is likely or an analogy might be being drawn. In such cases, we need to ask whether the evidence is good evidence for the conclusion or whether the analogy is fair. Is it relevant? Could it equally well point to the opposite of the conclusion?

Talk of logic and arguments and discussion of whether reasoning is good and bad generate a desire within some to switch off. These sound like issues which are arid, boring and irrelevant to what goes on in the real world. Almost any careful reading of a newspaper could challenge this response. If trains and birds are worthy of spotting, then so are logical howlers. If some stamps and books are collectable items, then so too are mistaken arguments of the great and the good. A collection of such arguments would show how some important – even life and death – positions are defended and how poor that defence can be. If the claim being put forward simply does not follow, if the reasoning does not stack up, or if a false assumption is being made, then you may challenge the argument. Of course, it does not show that the particular conclusion is false – there may be other arguments for the conclusion which do work – but you have been given no good reason to believe the conclusion so far.

For the first pages of our scrapbook of mistakes, let us simply note some typical bad moves and inconsistencies recently manifested in the quality press. Eagled-eyed observers might then wish to report their own sightings; categorisers might seek to classify accordingly. A couple of deliberate mistakes should even be found here within this article; of course, there could be plenty of unintentional mistakes, but being unintentional, the author would not know about them.

Misidentifications: the moral and the natural

Identification of the moral with the natural – or the assumption of a logical link between what is natural and what is right – is often to be found when people are supporting that of which they approve. We saw at the beginning how the natural is identified as the criterion for what it is right to do. Similarly, the unnatural is often viewed as indicating that the activity in question is bad. We find this as much in advertisements condemning unnatural food ingredients or shape of hair as we find in some moral condemnation of homosexuality or contraception. Curiously, when bicycles or medical operating theatres or anaesthetics are discussed, the charge of ‘unnatural’ is forgotten.

In one sense, bicycles, medical operating theatres and anaesthetics are as natural as wild flowers and earthquakes, if we simply mean by ‘natural’ that which is part of the physical and psychological universe. This would be in contrast to the supernatural, such as God, or abstract entities, such as numbers; again, in this sense, the natural would embrace both the good and the bad. In another sense, perhaps use of the word ‘natural’ is meant to indicate all and only that which does not involve changes brought about under a person’s will. In this sense once again it is easy to show that not all that is natural is good and not all that is unnatural is bad.

The bestial generates an intriguing element within the natural. Supporters of the natural as good often equate elsewhere some supposedly bad elements in people – sexual instincts, aggression – with the bestial; yet the bestial is, of course, part of the natural world.

Misidentifications: the moral and the religious

John Patten, the Secretary of State for Education – now, he is someone who should know better – has been the source of numerous reports and discussions concerned with the (alleged) decline in moral values, the decline being explained by reference to the decline in religious teaching in schools. Religious education, we are told, must be at the heart of any teaching of moral values; moral values, in some way, are grounded in the religious. Instead of looking to the natural, we are to turn our eyes to the spiritual in order to feel the force of morality.

Of course, just because both religious and moral values have declined simultaneously, it does not follow that one decline brought about the other – any more than it follows from the simultaneous decline in the popularity of Serbian soldiers and the decline in the value of sterling against the Deutsche mark that one has caused the other. Patten and others, though, suggest that what is good logically derives from religious values. Indeed, the concern for moral values is wheeled out to justify the promotion of religious belief; yet it is both a mistake to believe that morality can be grounded in religion and a danger to morality if people wrongly believe there to be such a link.

In order to spot the mistake, consider the following: is it right to save your neighbour from suffering because God ordains it or does God ordain it because it is right? If you are tempted by the first alternative, would you accept that even torture would be right, were God to ordain that? Presumably not – showing that being right is not dependent upon what God ordains.

The danger which results from people confusing moral values with religious values is more easily seen. News pages often tell of the (mis)understanding of right and wrong which may result from religious beliefs; an obvious example is the religious grounding which has created the bizarre claim that it is right that Salman Rushdie should be killed. More generally, if people have been misled into thinking morality requires religion, then once they lose their faith, everything becomes permitted; this is hardly an outcome sought by Mr. Patten.

God also regularly features in arguments designed to show that we ought not to practise euthanasia; we ought not – we are told – to put on a God-like cloak. In all consistency the defenders of this line of reasoning should either embrace the following argument or show how it differs from their reasoning.

“What are we doing these days, trying to save lives through famine relief work and AIDS research and sewing up wounded bodies? Don’t we realise that, by so doing, we are playing God? It is wrong for us to usurp the role of the Deity; further, it is not fair on us, having to take such momentous decisions.”

If – as I assume – most of us would reject such rhetoric and the implied conclusion over lifesaving, perhaps we should make determined efforts to show others their mistake in dealing out the ‘playing God’ card when assessing deathgiving. There are, indeed, genuinely difficult decisions over some life and death questions; they have to do with how best to act in the interests of the sufferer, not whether we dare or dare not, or should or should not, see ourselves as god-like.

Slippery Slopes

“Look how easy it is to slip from voluntary sex to rape. The only difference between the two is whether the woman freely consents, but we all know how grey this area is. There is date-rape and acquaintance-rape; there are cases of women being plied with drink, being persuaded against their will and not daring to say no for numerous reasons. So, once we accept that people may freely engage in sex, we are on the slippery slope to condoning rape – and that is the reason for not permitting sexual intercourse.”

Let us hope that those who are impressed by the slipperiness of slopes will not fall for this antisex argument. Just because there are grey areas, it does not follow that we cannot reasonably be defenders of willing sex and condemners of rape. True, no genuine instance of this slippery slope argument has been spied to date; but similar reasoning is sometimes presented against permitting voluntary euthanasia – and a similar response may be made to such arguments. We are often told in such reasoning that we would be entering upon a slippery slope; once killing is legitimised through euthanasia we are likely to find ourselves with something akin to a Nazi Holocaust. The response to this is that there is a distinction between the voluntary and the involuntary; so there would be no legitimacy in sliding from one to another – no more than there would be in the voluntary intercourse/rape case.

Some might accept the logical point above yet argue that as a matter of fact people would make the slide; again consistency would demand like reasoning over sex and rape. We might well think it right to give death to someone who wants it and in whose interests we are acting without thereby in any way being defenders of other killings; we could go out of our way to try to ensure that people do not confuse the two.

Matters Sexual

“Adultery is not a crime since loving is not a crime.”

Thus wrote Steven Berkhoff in the Guardian supporting adultery. Although this afforded a welcome change from the reasoning at the time leading to condemnation of David Mellor and others, it is not a great advance with regard to getting things right. In order to bring out the mistake, we might consider: cannibalism is not a crime since meat-eating is not a crime.

Talk of ‘crime’ muddies the water somewhat, for are we speaking of what is morally wrong or what is illegal? The two do not coincide, yet the law is sometimes invoked with regard to personal immorality and such immorality is often associated with sexual activity. Another recent example brings this out.

Who may view whom doing what to whom? When the doings are sexual, morality is wheeled out to justify prohibitions (just as religion is often wheeled out to justify morality), the recent wheelings being with regard to satellite television broadcasts of pornography. Lord Rees-Mogg likened scenes to ones of abattoirs’ butcheries. Assuming that all are acting freely and without harm (and we should need to discuss further any possible indirect harms), it is hard to understand how the configuration, location and number of simultaneous sexual acts and their observation raise issues of moral rightness or wrongness – though there are questions of taste and aesthetics.

In contrast, butcheries within abattoirs directly engage morality because of the suffering and death involved of the unwilling (albeit non-human) participants. So, while those who may be offended can easily avoid tuning into the sexual, there is a reason why even if we are going to be offended, we should be made more aware of the butcheries which we tolerate.

But doesn’t pornography deprave and corrupt? An attempt from a correspondent of The Independent set out to prove just that. The alleged proof is that people who have not been exposed to pornography would initially be shocked by it, but that repeated exposure leads to acceptance; therefore it depraves and corrupts.

What would such an argument-type lead us to conclude about normal sex, medical examinations, inter-racial marriages, slavery abolition, condoms, eating with a fork, Stravinsky’s Rite of Spring, heliocentricism – and the taste of Gorgonzola? All of these at various times have initially shocked, yet have subsequently been accepted. Have they depraved and corrupted?

On what is unsaid

Two doctors, writing in The Independent, argued that life-long monogamy prevents sexually-acquired AIDS because the risk of HIV infection is nil in uninfected people who have only had one uninfected partner. Assuming that this is true, what is not said is that equally the risk of HIV infection is presumably nil in uninfected people who have many uninfected partners. If the safety of life-long monogamy is assured for one couple, then it is assured for a thousand couples. If the thousand couples exchange sexual partners amongst themselves, it remains assured for them; so the monogamy falls out of the story as being inessential.

* * *

The examples above form a rag-bag of mistakes. Such mistakes have been identified in the philosophical literature over the years; though sometimes they give rise to sophisticated attempts at defence. There has been a thread so far in the collection, one constituted by the concern for morality, but mistakes are to be spotted anywhere, though the sports pages remain untested for this.

In conclusion, we may note that an argument can lead to surprising discoveries; the following flows from a British Telecom advertisement a couple of years ago about its price changes.

Although the price of local calls increased by 5%, this – BT told us – was actually a decrease, being below the retail price increase of 5.8%. So, a company whose prices increase by (say) 10% is actually increasing by only 4.2%. In view of this, we can conclude that the Actual Retail Price Increase (ARPI) is, well, 0% and will forever so be. BT clearly provided a valuable service to the nation by thus solving the problem of inflation.

Spot the mistake.

© Peter Cave 1994

Peter Cave teaches financial planning to pinstriped-suited investors at the City University and philosophy to jeans-clad students via the Open University.

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