For example, think back to the last time that your mother tried to line you up on a date. She told you that your future date was "cute" and "fun" and "interesting". It was a disaster because your mother's definitions of those words are very different from your own. Her idea of interesting might be talking about the merits of cross-cutting vs. mulching your lawn, but that does not mean that you want to talk about turf management all night with your date.

The former is a silly example. Serious examples abound. The word "freedom" means something very different to me than it does to somebody in Serbia right now. Freedom in my vocabulary means no papers to grade, no homework, no work. Freedom to them might mean walking to the corner bread store without getting shot. When George W. Bush uses the word liberal he means something very different than somebody from the Democratic party using the word liberal.

When constructing any piece of writing, you need to ask yourself whether or not your audience is going to define abstractions in the same way that you are. Don't assume that they are. It is much safer and more interesting (did you catch that abstraction?) to use examples or concrete illustrations or analogies (extended comparisons) to show the reader what your mean.

An abstraction like "beauty" tells the reader something about your statement, but does not show them anything. They are going to be much less likely to get the point that you are trying to make or to be persuaded by you if you don't provide the common ground of a shared definition of your abstraction.

Go to the Eliminating Abstractions exercise for some practice recognizing and illustrating abstractions.