The webcomic xkcd posted a comic a while ago that explains rocket science using “only the ten hundred words people use the most often.” It’s a great idea, and clearly the creator thought so too, since he’s now writing an entire book around the concept. He has also made freely available a tool that allows you to write using only those one thousand most common words.
Here is the first sentence of an old post (Animal visual illusions), as I originally wrote it: “Animals interact visually all the time.” Here is the same sentence rewritten using only those thousand most common words: “Animals do things with each other using what their eyes see all the time.” The second version is much harder to understand; there is definitely value in having more than a thousand words to work with.
But what about words that don’t represent some especially nuanced or complex concept, but exist for the sake of specificity: labels, like bird species names? Dark-eyed Junco does not pass muster in the xkcd word checker tool, unsurprisingly. I can get as far as Dark eyed small brown bird that jumps along the ground and has white on the outside of its — but now I’m in trouble: tail isn’t allowed; neither is butt feathers or bottom fan. I have to switch directions and go instead with: Dark eyed small brown bird that jumps along the ground and has a white stomach and black head and looks round in the cold.