One step at a time

The cartoon below illustrates humorously how abstractions (or building blocks on top of the other to make something more powerful) can lead to very powerful things.

Source

If you think about it, nobody could have envisioned and built the modern computer (or any great human artifact) in a single go without going through the iterations. It was always small steps rather than large leaps. Many times, there would be multiple approaches in the marketplace which leads to competition and ultimately a winner based on merits.

This process is very much akin to evolution in nature. When you read about nature's creations, you wonder how such complex beings could have been designed by evolution. For e.g. see the digestive system of a cow http://www2.kenyon.edu/projects/farmschool/food/milkbio.htm.

But if you think about them as abstractions built on top of each other over millions of years, its a little easier to imagine.