Gestalt Principles

• Similarity
(Elements that look similar are perceived to have the same function, ie shape size or color - guess my first guess was close)
• Proximity
(Elements that are close together appear to be more related than things that are spaced further apart)
• Common Region
(Elements located within the same area are perceived to be grouped together)

How humans group similar elements, recognize patterns, and simplify complex images when we perceive objects (maybe a scene or picture would be better phrasing there, dunno, not my idea. I think object and i'm immediately trying to picture which language i'm coding it in... unless it's a 3D object, then there's vertices, lines and triangles.)

My first guess was shape, color, pattern. Don't know much about it, I admit...