I'm not sure they can work alongside each other that easily. often the logical choice is not the same as the emotional one.
I tend to approach life very logically, seeing things very distinctly as black and white.
some times its helpful: recognising someones worth/use even if i dislike them
sometimes not so much: chosing/dismissing someone for a perfectly sound logical reason when it's not polite/right to do so. i'm particularly bad at doing this with friends when the 'emotional' choice is to chose either a close friend or someone who really wants it but the most logical choice is someone else entirely.
it's problematic, it upsets people when you decide things based entirely on logic without any kind of emotion at all.
i remember my mom getting upset when i said that yes if stranded on a desert island with no food etc and she were dead i would eat her as a last resort. (xmas drinking leads to weird places...) the point is in this oddly specific hypothetical situation most peoples emotional response is to shy away from what you know to be logically sound reasoning.
of course everyday living doesn't tend to be life and death survival but the same is applicable.
it's frustrating to a logical person when others let their emotions guide them down what (to us) is clearly a stupid path.
and emotional people get upset and annoyed with us for having little to no regard for the emotions of others.
obviously thats more in the extremes, the majority of people though they tend to lean more to one side than the other have a healthy dose of both emotional and logical reasoning....