When teaching students critical reasoning it is an article of faith that we should teach them logic. Of course, we ameliorate any benefit this might have by teaching it incomprehensibly and in artificial cases. But still, we believe logic is what is most important in philosophy and in culture generally.
Ah, culture… in which someone who wishes to assert that a position is wrong says it is “illogical”, when of course they mean “unsound” or “badly founded”. Where logic is held to be, in shows ranging from Star Trek to Fringe, the antithesis of logic, despite Hume’s dictum: “Reason is, and ought only to be the slave of the passions, and can never pretend to any other office than to serve and obey them.” (Treatise p415).
So, what is logic good for? Does it prohibit certain conclusions as “irrational” or “illogical” in themselves? The answer is, of course, subtle and complex, but there is a simple enough answer: logic is for transferring the truth of your premises to the conclusion, and nothing is, in itself, irrational or illogical. So I put up a conundrum, a seeming paradox. Is logic truth achieving or not? Are views ever irrational? Let’s see…
In logic, a premise is an assumed starting point. It is a sentence that asserts or denies some state of affairs. Swearing, for example, when you hit your thumb with a hammer, can never be a premise. But the sentence, “I hit my thumb with the hammer” is a sentence that asserts some claim or state of affairs (I’ll get to that locution in a bit), and so it can be a premise. For example:
P1 – I hit my thumb with a hammer
P2 – If I hit my thumb with a hammer, I will swear
C – I swore.
From the truth of the first premise P1, and the truth of the conditional, or hypothetical, or counterfactual, sentence of P2, what I will do if P1 is true, I can conclude (or predict) that the conclusion C is true. Seems simple enough, right? Well in simple inferences (arguments, as they are called. In logic, an argument does not involve the passions!), it is. But get into a real world argument and things get a lot more troublesome.
The point of logic is that if you have true premises and your argument is logically correct, then the conclusion must be true, and you are irrational if you admit both that the premises are true and the argument is correct, but the conclusion is false. This is obvious on reflection. A rational person accepts these “sound” arguments as giving the truth. What Spock ought to have been saying all those episodes is that the reasoning he was objecting to was “irrational”.
Arguments, though, in themselves, are never true or false. They are at best valid (meaning, the logic is correct). And as the truth of the premises depends upon the agreement of the persons arguing (we sometimes call these agreed premises), it may be that a valid argument does not give you a true conclusion, because in fact the premises are not themselves true – they might be falsely thought to be true by both sides, or they may be vague, or they may be open to several interpretations. And here is a problem that I have encountered in philosophy.
Consider one of the most influential books on politics ever written: Robert Nozick’s Anarchy, State and Utopia (1974). Nozich begins with a main premise:
Individuals have rights and there are things no person or group may do to them (without violating their rights). [p ix]
and from this concludes
Taxation of earnings from labor is on a par with forced labor. Seizing the results of someone’s labor is equivalent to seizing hours from him and directing him to carry on various activities. [p169]
In effect, he argues, taxation is a form of slavery.
Now Nozick’s arguments are valid enough. He interprets each of his steps in a way that the conclusion is forced. But is it irrational of me to think that taxation is not slavery? I think it is not. I dispute several of Nozick’s interpretations. For a start, I do not think rights are natural or immutable. Moreover, I think that governments should be involved in setting up infrastructure, and paying for it from taxation. It all depends upon how you interprets “rights” and “government”. I mention this particular example because Nozick’s arguments developed into a foundation for what is now called “neo-liberalism” or “neo-conservatism”, and which has driven far too many governments to lessen taxes for the public good infrastructure in favour of a choice-driven “user-pays” model over the past 35 years. It supports, for example, the “austerity” model of economics.
Why has a good philosopher and logical reasoner comes to such a strange conclusion? In part it is because he uses logic as a tool for finding the truth without at any point stepping back to consider the real world implications. The arguments are valid, but the premises are not true, or are at best interpretable in various ways, only some of which lead to the conclusion (as a side note, Nozick relies on the “social contract” theory of the state, which is in my opinion, and it is a grounded but not obvious one, false: no society has ever been founded upon the tacit or explicit agreement of its members).
Take for example, someone who was not born in an atheist home, or a religious home, free from even hearing about religion and coincidentally he made up none of his own. Then when this man hit 21 years of age he was exposed to our world of countless religions. This man has no connection to any religion in particular and he is asked to pick one or none of them. He would notice that they are all mutually exclusive, that is no two religions can be right. He would also not be able to determine which had any validity. All he could do was read the old religious scriptures, which unfortunately almost every religion has. You could say that he could judge validity based on the most popular religion, however would you base it on people alive or people dead? Really the most popular religion of all time would not necessarily be around today, though the consensus today would be that it was ridiculous and unbelievable. This being the case, it is illogical to be religious. If someone who has never been exposed to religion comes in when he is 21 (so his brain has developed enough to make a conscious decision) and cannot make a rational decision which religion is right, that means there is not enough logic behind religion to make it a rational decision. [From here]
The view that because there are no reasons (of a certain kind) to choose a particular religion, therefore religious belief is illogical, is a total non sequitur: it does not follow. For a start, one might challenge the view that those are the only reasons for choosing a religion (they are basically empiricist assumptions that only through observation and testing are beliefs rational or logical), which Hume’s dictum denies. Secondly, it requires a notion of “rational” that no real human ever can satisfy – everyone begins their reasonings with some values or sets of beliefs that they did not acquire through reasoning. And so on. [Note: I am not arguing that religion is the best conclusion here, as I clearly do not think it is. I am talking about reasoning, not religion.]
One way to guard against conclusions that are not themselves warranted just by reasoning is to do “reality checks” along the way. The more outlandish the conclusion, the more you must examine each and every premise, and all the alternatives to it, and here is where “being logical” and “being rational” are at their most vulnerable. For some premises, any conclusion can be shown to follow validly, and where premises are not themselves supposed to be founded upon empirical (that is, publicly verifiable) data, it can easily be logical to be a libertarian or a believer in fundamentalist religion or even a belieber.
Reasoning works best when both sides test their assumptions and defend them, and the logical aspect of the arguments become just the background methodology of the argument. It is, I consider, most rational to argue opposing views to the point where all the premises are well examined and interpreted, even if logic alone will not get a resolution. In the end, the only beliefs that are “logical” are those that rest upon logical validity, and that can be manufactured upon demand. And the only beliefs that are rational are those where the argument is valid and the premises are at least plausible to the arguers. If, as often happens, an impasse is reached, then as Wittgenstein wrote:
Where two principles really do meet which cannot be reconciled with one another, then each man declares the other a fool and an heretic. [On Certainty 611]