I am not sure that computer technology would have become powerful, inexpensive, and ubiquitous to the extent that it is become today were his aunt and his cousi

I am not sure that computer technology would have become powerful, inexpensive, and ubiquitous to the extent that it is become today were his aunt and his cousin correct. The aunt and the cousin are thinking that 'computer technology' exists at the level of abstraction of the sandcastles in the metaphor. To some extent it does, but the vastly greater part of it is at the level of abstraction of the knowledge and theory of building sand castles, as gained over the course of many iterations. One of the most common themes one hears, when reading what people write about computer science, is how few new ideas in computer science are actually involved in nearly anything anyone does on a computer (or teaches at the undergraduate level).