Let me quote the book:
"Because Rationals value the strategic intellect so highly, the tend to take as their idol the technological wizard, especially the scientific genius. After all, a wizard is the ultimate scientist, with what seems an almost magical power over nature, and in single-minded pursuit of the four aims of science: the prediction and control of events, and the understanding and explanation of their contexts."
Yeah, that. Granted, a rational person might not be strictly scientific, but only "scientific" in the humblest of senses: observation. See, that's what science is at its base point. It's looking, observing, and making conclusions based on what one has observed. It is not a tall man in a white coat staring at beakers of colored liquid. It's not a giant jellyfish of knowledge that will punish you for saying or doing something "unscientific". Human understanding is limited, and thus we must with the most childlike, humble observation go forward in science, allowing our old notions to be wrong if experience shows that to be the case. So, a child playing with a faucet is science, because the child is observing and coming to conclusions about a small piece of the world: a sink where he is taking a bath.
But beyond that, Istari!
The especially nerdy among you will know that they are the wizards in Lord of the Rings, as mentioned in the appendices after Return of the King. According to JRR Tolkien, these are Maiar, spirit beings below the Valar, the supreme servants of Iluvatar. Certain Maiar, known as Istari, were sent to Middle Earth to influence it for the better, and in particular to stop Melkor and Sauron.
Don't lose me now, alright? I know we're talking about very nerdy matters, but if you've come to this blog expecting something not nerdy, then you're in the wrong place.
In any case, there's an important difference in the Istari than in other wizards. Harry Potter, for example, is defined by his magic: he does it constantly and for various purposes. The Istari are not magicians, though. A guy reviewing the Lord of the Rings movies rightly commented that Gandalf never really used his magic for anything. What this reviewer apparently didn't realize is that this is the fault of the book, not the movie.
Let's look at Gandalf (book version -- the movie version doesn't count). Think of a time when he uses his magic. He uses it primarily to light his staff as a torch in the caves, and also to light a fire on Caradhras. He never shoots magic beams at anything, or turns someone into stone. Think then how he actually does help others. He talks. He sends messages, guides others, goes for guidance himself, researches magical power, and stirs up reluctant powers to help greater causes.
One of the parts of the movie that offended me the most was the "exorcism" of Theoden. In the book, Gandalf doesn't "magic" the troubles out of him, because Theoden's troubles are years of being told negative things, not magic. Thus it's with words that Gandalf gently brings him out of it, and the reader feels with Theoden his gaining of strength.
Actually, while we're at it, let's look at Saruman. He also never uses magic to zap things. He's noted for his ability to speak, and how he uses it to manipulate others. And when Saruman wants something done, how does he do it? By getting orcs to build machines. Saruman used gunpowder bombs, not magical words, to attack at Helm's deep.
So what's the point of mentioning these things? Simple. Everything Gandalf and Saruman do is applicable to real life. We can either be a wise, powerful advisor, or a malevolent powermonger using one's natural abilities to get what we want. We can encourage, manipulate, aid, steal, empower, or brainwash at our leisure.
This is the peril of the Rational. The INTPs, ENTPs, INTJs, and ENTJs, the wizards of Myers-Briggs, are mighty of mind, as we observe the way the world is and learn to see things that other personalities might not. We see life at its largest scope, ready to make and entertain theories on why everything is. It doesn't help that we are more interested than most about things like science, history, the intricacies of language, and computer technology. We want to know why things are, and because others find different pursuits more interesting, we are capable of manipulating those who aren't so interested into thinking the way we do, because they trust our intelligence, even when they don't like us.
There are two main differences between Saruman and Gandalf we need to be aware of. They have different perspectives on power. This is very important to remember, Rational ones: we are not leaders. Oh sure, we lead in one sense, but leadership in and of itself, defined as the ability to get others to follow you, is its own talent, and we musn't make presumptions on our ability to lead.
Notice Gandalf. He at most leads the company of dwarves in The Hobbit, and the fellowship in the first part of Lord of the Rings. He's not a king, a steward, a president or prime minister. Sure, he advises all sorts of leaders, but he has no eye on any throne. Saruman, on the other hand, sees his mental abilities as proof he is greater than those that surround him, and thus has every right to rule.
The intellectual's mind entitles him to the work of his hands, nothing more. In fact, fear of intellectuals and intellectualism peaked in the mid twentieth century because of intellectuals. It was many intellectuals (Marx gets too much credit) who created communism and thus became the killers of millions. Hitler's Germany was a huge social experiment. Well-meaning (and "well-meaning") progressives use forced goodwill to obligate others to involve themselves in their causes, giving greater power to the government to mess with the economy and create dependency.
That's the reason why Rationals are only around 10% of a population. Our ideas create worlds, but they also destroy old ones. Depending on the quality of the old or the new (nothing is good simply by being old or new), this can be either great, or devastating, particularly if we assume our intelligence is so great that we can handle the consequences or that those consequences won't happen.
Something I feel is true, but cannot conclusively prove, is that most Rationals should not be direct leaders. Oh sure, maybe of small groups, but there should always be a part of us that says, "Okay, I'm going to put your reasoning alongside my own" or "your opinion matters too." Thing is, even though a Rational may be technically correct, we don't take into account that people are moved often by emotion, or simply by previously held beliefs, so that our correct answers don't matter to them unless we can convince or trick others into going for it. And you know what? We're not always correct. A rational answer may be good, but there's the unpredictability factor of others that skews our results.
So in short, Rationals are best at being advisors, or pursuing specific courses of study and making that knowledge available to others. We're great at getting things done, but because leadership is not our talent, we aren't the best people for the job. In my hypothesis, we are generally good for being advisors, and putting other people more deserving in power. This giving of power reminds us of our humility, and because of our observation and studies, those of us who prefer history or social science are good at knowing who should lead. And those of us who are better at mechanical/chemical science at least know which leaders will allow science to progress.
However, like I said before, this is my hypothesis. I haven't done any studies on the leadership capabilities of Rationals, just some reading here or there. Still, it's generally good for us to remember humility, that just because we are talented in gathering knowledge doesn't mean we're talented in everything.
My hypothesis is in a way supported by David Keirsey, who, when mentioning the Rational as a parent, says that we are "Individuators". That means as parents we allow children to develop their unique selves and blossom in their particular talents. If we treat adults similarly, it means that we know who among us is useful for what.
In any case, the Rational is a powerful being, with the ability to influence others to great good or great evil. Sure, that's a bit of a melodramatic way to put us, but it's true. Primarily because people only get so many talents, and when our talents are intellectual more than practical, we have to make use for ourselves somehow.