|Humans are pretty amazing creatures. One of the most interesting and powerful things about humans are their eyes. It is not only that humans have keen vision, but it is the way that humans give meaning to the things they see.
For example, which one of these blocks is most important? Humans don't just see six identical baby blue blocks. Instead most humans see the baby blue block on top as the premier block because it is positioned head and shoulders above all the other blue blocks. To humans, position has meaning. And most humans interpret height as importance, ie. King of the Mountain. So verticality (height) is one way of indicating meaning by position.
Some people might also say (rightly) that the bottom baby blue blocks are most important since they are the foundation upon which all the others rest. Where is another way of conveying meaning through position.
Which of these blocks is most important? Here we are looking at centrality, where the center position is perceived as most important. The spokes radiating out from the central hub do a lot to create the meaning. Lines and arrows are great tools to use to help a viewer understand the meaning you are trying to convey.
Size is another way to convey meaning. Obviously these circles are not equal. The eye generally follows a "more is better" strategy. But in this case, color makes a big difference. If these three circles were all the same color, not only would the picture be a lot less interesting, but the big circle would be even more dominant. So color is another useful tool in conveying meaning through diagrams.
By overlapping the same three circles from above, we do several things to the way most people will interpret this drawing. Now which is most important? And what is the relationship between the three circles?
Now the small purple circle is on top of a stack of circles. It is small but it has vertical importance. The green circle is big and it is at the foundation. So these little shapes start to be able to communicate quite a bit. Add a few labels to the diagram and you can say quite a lot.
When you start using many of these visual tricks, you can start to say big things with few or no words.
Which of our visual tricks ar used in this last diagram? (verticality, centrality, foundation, size, color, overlap, lines and arrows?)