It seems unlikely that, for anyone alive today, the world is exactly the way they wish it would be in every detail. Because there is discordance between what is the case and what we wish the case would be, we all engage at some point in time in wishful thinking: the desire that our situation be something other than it really is.
There is certainly nothing wrong with this, and it can manifest in any number of ways — for example, in the daydreams which inspire us to make the necessary changes so that our lives will be more as we desire. When it comes to logical arguments, however, wishful thinking can create problems by blinding us to unpleasant truths and getting us to believe as true things which have little or no connection to reality.
One way in which wishful thinking can be seen in arguments is through the process of rationalization — a perversion of rational arguments in defense of an idea which you should know better than to accept and defend.
When we rationalize things, we are trying to show that it is rational to believe something we wish were true, but which in reality isn’t true and isn’t actually rational to believe. Rationalizations are common and appealing because they serve as effective means by which we can continue to believe things that make us comfortable while appearing to the whole world — and in particular to ourselves — as rational people. In other words, we appear to believe something because it is rational to do so, not because we simply want our beliefs to be true.
For example, there are people who indulge in too much alcohol, excessive drugs, smoking, poor foods, etc. while also claiming that none of it has ill effects on their health. Perhaps there are a few rare individuals out there for whom that may be true, but for the average person exactly the opposite will be the case — and when such a person offers lame arguments in defense of their claim, they are engaging in rationalizations designed to defend a belief which is based upon wishful thinking and not reality or reason.
Wishful thinking is dangerous because it impairs our ability to properly see and understand reality. There is a reason why our senses generally give us accurate information about the world around us: without accurate information, we couldn’t hope to navigate our world with any expectation of safety or success. We need to know what is going on around us if we are going to avoid danger or take advantage of opportunities.
We cannot do so, however, when our beliefs about that world are being founded upon what we wish the world were like rather than what the world really is. It’s even worse when we attempt to convince others to join us in our delusions, as if our beliefs about reality were in any way a means of changing the world into something else. Beliefs can be the cause of actions which in turn can change reality, but beliefs and wishes alone never managed to effect real innovations or transformations.
We can avoid the infection of wishful thinking in our own arguments by trying to stay attuned to what our wishes are, and thus how they might diverge from reality. If we acknowledge that we all are susceptible to wishful thinking, we may have an easier time forestalling it in what we say and write. Should we encounter this in the arguments of another, getting past it might be more difficult. It is rarely easy to get a person to see that their arguments are really rationalizations and that their wishes are not reality.
Such individuals have, almost by definition, convinced themselves that they are offering rational beliefs for empirical facts. Acknowledging that they are not is a twofold defeat: not only must they admit that they are wrong, but they must also admit that they somehow managed to engage in self-deception. But who wants to be guilty of that? This is an additional motive one may have to resist your critiques; the only way around this is to find some means of correcting them without bruising their ego, and by giving them a way to change their mind without having to admit quite so much error.
If they really do want to be as rational as they are trying to portray themselves, then eventually they will be able to look back and accept the presence of rationalization and self-deception without it being so difficult. In the meantime, however, a bit of compassion and understanding on your part will go a long way towards helping them get past their rationalizations and back on track to more defensible beliefs.
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