“When we’re talking primarily about good typographical rules and creating a balanced visual hierarchy, those things are not subjective. Those just are. You can guarantee that people will react a certain way to these things. And we’re not actually looking for an emotional connection where we might be with color and the more artistic layer if you will. That’s the nice thing about design. At its core level it’s not really subjective. It’s just a matter of good balanced decision making and not cluttering things, not overcrowding.” — Dan Rubin
Design is empathy, psychology, and basically understanding how people think.