I’m trying to illustrate the notion that things that are conceptually simple are oftentimes extremely complex to implement for a variety of reasons. The problem is, I can’t think of a specific example. At first I was going to go with moving a pile of sand with tweezers, but then I realized that that is conceptually and practically simple–using tweezers to move sand is easy, but prohibitively tedious.
What are some examples of simple ideas that are hard to implement?
How about clicking a link on a web page. Conceptually, all you have to do is move your mouse there and click.
But in actuality[ol]
ETA: And of course all this ignores the mouse itself, peripheral protocols like PS/2 or USB, device drivers, opposable thumbs, the neural pathways, motor skills, nerve impulses and so forth necessary for moving and clicking a mouse, the development of reason, the evolution of mankind, the origin of life on Earth, the origin of the Earth in the Universe, the Big Bang, and for some reason the Muppets.