Despite what we like to think, our emotions guide most of our decisions, big or small. Humans are so emotionally driven that we cannot think without emotion, no matter how objective we try to be. Every single experience we face in our lives impacts all future experiences and choices, even if we don’t consciously realize it.
In rhetoric, the appeal to the emotions (or pathos, if you want the technical term) can be used to your advantage. Often emotional appeals are more influential than spouting off statistics, unless the way your state your statistics has an emotional connotation. Saying “number of dead babies” is infinitely more emotionally loaded than saying “infant mortality rate,” though you might want to consider your context and your audience when using such words. Appeals to the emotion can be useful, but careful that you’re also keeping a professional ethos so your argument are actually taken seriously rather than your audience being disgusted with you.
So hand in hand with pathos is the consideration of kairos. Your context, your audience and their maturity level all go into what kind of emotional appeals you can make, or if you can make explicit emotional appeals at all.
But keep in mind that emotions drive everything we do, even the smallest bit. The right placed word can be the difference between effective persuasion and having your argument be completely dismissed or ignored.
Emotions are powerful things, never to be forgotten.