A further note on the application of deductive arguments (Now playing Jesse Hold On by B-witched)
Introduction
This short article is an extension on the earlier article, Why am I a Christian. In that article, I made a point that all scientific arguments are inductive. The reason is because science is knowledge expanding, which inductive arguments are of such. Deductive reasoning, on the other hand, are knowledge preserving; the conclusion does not tell us more than what is already implied in the premises.
One question that I have asked during my first year undergraduate days is, "What then is the use of formulating a deductive argument?" The answer is that the process is valuable in separating valid arguments from invalid ones. Good logical thinking means you must be able to analyze the different arguments that we often hear and read about. For example, in the Straits Times, we are confronted with different kind of arguments. Being able to analyze an argument in terms of premises and conclusions will enable us to better assess their validity. This is the same reasoning used by economists who insist on the using of formal mathematical models, the theory of sets is particularly emphasized, in analyzing any issue. Mathematics is pure logical reasoning and utilizing mathematics in economics will let us be aware of our thought processes better than hiding behind literary words, words which often hide some crucial assumptions that are necessary for their arguments.
Example 1:How does the silent majority thinks?
To give an example, Singaporeans who proposed some 'radical' policies for Singapore to adopt are often told that they only represent a small elite; thus not representing the majority of Singaporeans. The recent exchange of ideas between Cherian George and the PM's Press Secretary, Ong Keng Yong illustrated such a point. In Keng Yong's reply to Cherian George, he said:
"The participants of dialogues and Internet chat that Mr George quoted are a small elite. They do not represent the general population or ground sentiments."
Upon taking a closer examination of such arguments, the structure is:
P1: There is a small group of elite Singaporeans who are the vocal minority
P2: There is a corresponding large group of Singaporeans who are the silent majority
P3: 'Vocal' is the opposite of 'silent'
P4: 'Minority' is the opposite of majority'
Final Conclusion: Thus, the silent majority's viewpoint is also opposite to the viewpoint of these small elite.
Breaking up the argument in this form allows us to see a potential flaw. Even though I may accept all the four premises, the conclusion may not follow from them. The silent majority may have the same viewpoint as the vocal elite but they choose not to voice it out for other reasons, like rational ignorance, bread and butter issues or political apathy. The argument is assuming that, just because P3 and P4 are true by definition, the conclusion necessarily holds.
To be fair, this argument is not really a deductive argument, rather it is an argument from analogy, which is an inductive argument. It is similar to the argument between shaving cream and whipped cream. The above argument by Keng Yong has this kind of form:
Object X has characteristics a and b
Object Y have the characteristics ~a and ~ b(~ means negation, i.e. not a, not b)
Object X has a particular characteristic c
Therefore, Object Y also has the characteristic ~c
Thus this argument is automatically invalid as a deductive argument, just like the argument for Christianity. As an inductive argument, it really depends on how much 'faith' you have on the views of this 'silent majority'. I have given a reason above where the conclusion need not hold.
Example 2: The Speak Mandarin Campaign
Another point that illustrates the usefulness of deductive reasoning is in analyzing the annual 'Speak Mandarin Campaigns'. It was supposed to be an annual affair, although I suspect that, with the present policy of discouraging Singlish, this campaign will be more low-key from now on. The slogans that they used have varied over the years but I found one of them particularly offensive, the slogan goes something like this:
"If you are a Chinese, make a statement in Mandarin"
Now I cannot remember which year this was, it was the one I think where they got people like Ang Peng Siong and Catherine Lim to promote this slogan.
Now, why did I find this particular slogan offensive? Well, before I went complaining to people about it, let us first examine what interpretations this slogan does not imply. I figure I need to get my facts right before venting it off, in case I was shown to be wrong. Firstly, this slogan does not imply that, if I am not a Chinese, I cannot make a statement in Mandarin, this is the fallacy of denying the antecedent. Secondly, this slogan does not imply that, if I make a statement in Mandarin, I must be a Chinese, this is the fallacy of affirming the consequent. What this slogan does imply is this: If you do not make statements in Mandarin, you are not a Chinese. The Latin name for this kind of reasoning is modus tollens, which has this form:
If P then Q
Not Q
Therefore Not P
If we accept the 2 premises as true, we necessarily have to accept the conclusion. Modus tollens is often used to falsify scientific hypotheses. Whereas, denying the antecedent has this form:
If P then Q
Not P
Therefore, not Q
Even if I accept the 2 premises, I need not accept the conclusion. The same goes for the fallacy of affirming the consequent, again, these points should be familiar to any attentive first year student in a logic or a critical thinking class. Interested readers are again encouraged to refer to Elements of Sentence Logic by Wayne Patterson.
Thus, you can now see why I was particularly disturbed by this slogan. I do not see how I should be told what language I should or should not speak. No doubt my Mandarin has been bad ever since secondary school, but this is the wrong way of encouraging me to strengthen my Mandarin beyond the lau3 ying1 zhua1 xiao3 ci1 (Translated literally as Old Eagle Catch Small Chick) level :-). In fact, I would hypothesize that, one of the main reasons why many Singaporeans are neither speaking Mandarin nor English well, going by the policy of discouraging Singlish, is that our language policy keep changing over the year; we are caught between the dilemma of Singaporeans being increasingly westernized by the usage of English and the economic need to be proficient in it. We thus become a jack of all languages but master of none.
Conclusion
These are just two examples I have selected to illustrate the power of logical thinking, I am sure you can think of many more. Now go and think!