Original Post: 14 April 2012
Posted Here: 5 December 2017

In my post on Names and Definitions, I pointed out that when we define something we set limits as to what it is and what it isn’t. Part of the process involves providing names for the things of interest. I also pointed out that we sometimes confuse the name and the definition by thinking that the name is the definition. Giving something a name is much easier than giving it a definition.

When we set limits in our definitions, we are essentially drawing lines to separate one thing from another. Sometimes this is easy to do. Sometimes it us easier said than done.

circleFor example, a circle is easy to define: A circle is a line where all the points are the same distance from another point called the center. Not all words and concepts are so easily defined.

My dictionary defines “night” as “1a. The period between sunset and sunrise, especially the hours of darkness.” The first part of this definition draws a line between day and night, with night being strictly the time between sunset and sunrise. But the second portion is a bit ambiguous.

If I asked you to go outside a few minutes after sunset, then come back and tell me if it was day or night, you might be reluctant to tell me that it was night because it was still very much light out there. You probably prefer the second portion of the definition, which refers to actual darkness.

nightIf I asked you to go out around midnight, you would not hesitate to come back and tell me that it was night. Likewise, if I asked you to go out around 9 or 10 PM, or 3 or 4 AM. But the closer to sunrise or sunset it was when I asked you to go out, the more you might hesitate about saying that it is night. You’d probably have some trouble stating the exact time that it became or stopped being night.

Many definitions seem to have a twilight zone around them unless we make some arbitrary definition, like the dictionary did with its first part of the definition of “night.”

Supreme Court Justice Potter StewartWe tend to fall back on definitions like Supreme Court Justice Potter Stewart’s famous definition of “pornography” in 1964 – “I know it when I see it.” The biological definition of “species” was once one of those definitions like “circle” where a definite line could be drawn between species. Now we can only say “I know it when I see it” if we want to put a name on a species. The same is true for definitions of “life” and “science fiction.” We can always come up with some arbitrary line in the sand to allow us to create a true definition. But this can easily lead to confusion and controversy—like the definition of “planet” which “demoted” Pluto, and, according to some astronomers, should have done the same thing for Earth.

I’ll return to the definitions of “life” and “science fiction” in future posts since, as a science fiction writer, I find both topics fascinating and important to my work.

Keep reading/keep writing – Jack