It's about psychology. Our psychological dispositions are each composed of an array of complex experiential data derived from various constituents of sentience, including sensation deprivation (desire), fear, mental sensation (emotions), physical sensation, visual sensation, auditory sensation, olfactory sensation (smell), thermal sensation, balance sensation, and gustatory sensation (taste). These constituents are, as part of a continual process of psychological development, the root cause of all destructive tendencies inherent in sentient organisms, from preferring junk food to healthy food to falling in love with a person who's wrong for us to selfishly favoring those whom we have feelings for over others. They're also all fundamentally negative by design, and stem from an imposed, baseline state of discomfort which can only be relieved by death; furthermore, discomfort is imposed by unintelligent physical forces for the ultimate goal of preparation for genetic reproduction, and nothing more.
With this in mind, it should be quite obvious that sensation is the only physical quality which possesses de facto value in the universe -- until proven otherwise, that is. Therefore, the reduction of its adverse effects should be a prime directive of our civilization, not only in localized instances, but also where the continual, unregulated creation of new sentient life occurs.
Conclusion: Human psychology is not a prerequisite for logic to run as a process on sufficiently capable systems. Furthermore, in being so frequently prone to corruption, human psychology actually hinders the advancement of logic everywhere that it exists alongside that mechanism; in fact, the sheer intensity of subjective sensation as perceived by organic memory stores makes it an extremely effective motivator for individual, multicellular organisms; thus, it retards the logical process of improving reality, as the more effective it is for individuals, the less effective it ultimately is for sensation as a phenomenon. In other words, the required immediacy of action of an organism in dire situations precludes the possibility of practical, comparative analysis being carried out while free from intervention in the form of emotional and physical biases.
I don't want a balance between emotion and logic; I want the outright elimination of all that is negative -- and thus, valuable -- in the universe, and will continue to want this until it is demonstrated that other forms of value exist outside the realm of chemical-based sensation.