I would take the ying yang approach and say that no matter how much someone tries to think about things rationally, there'll always be at least a bit of emotion in that person, we're human not computers. That person doesn't necessarily have to act on those emotions but they will still be there. Conversely, someone who appears to do everything because they feel like it, will have some level of rational behind their actions, we're human not animals.
I agree with everything you said... And I wish you were the real Giovanni 0.0 You are so perfect for that roooole....
There are two things I want to comment on here:
1) Humans are, as described above, a proper mixture of various things. This is a common theme throughout fantasy settings where humans are described as the weakest overall but they are able to use ALL their traits with more potential. This allows them to be the leaders, in most cases, of all races, because they are able to understand and unite all races under their banner.
At the same time, however...
2) It is believed by many that humans are made up of only Yin and Yang. The problem with the Apollonian and Dionysian concept is that it places all manner of chaos and discord into Yin - this is not the case. In fact, despite researching Yin and Yang for quite an amount, I did not know of the "third force" until I researched Pokemon. Odd, right? Zekrom represents Yin. Reshiram represents Yang. Kyurem represents Wuji. While Yin and Yang are for Order, Wuji is for Chaos. Only with Order and Chaos combined is there true Balance (according to the Guthixian).
Thus, we humans are made up of not only Yin and Yang, Apollonia and Dionysia, but also some kind of chaotic nature. Yang still represents light, order (in a societal sense), and structure, while Yin still represents dark, disorder (also in a societal sense), and emotion. However, these two are still very controlled when compared to Wuji, which represents void, primordial nature, and constant change.
^ A good example of this is to say, in The Secret World, that the Templar are Yang, the Illuminati are Yin, and the Dragon are Wuji.
In truth, the Illuminati were Yang, the Templar were Yin, and Anonymous is...still Wuji.
Point being, to say that emotion is simply chaotic or that logic dictates true balance...such things are wrong, I believe.