Thompson and Ritchie were among the first to realize that hardware and compiler technology had become good enough that an entire operating system could be written in C, and by 1978 the whole environment had been successfully ported to several machines of different types.
Eric S. RaymondA software system is transparent when you can look at it and immediately see what is going on. It is simple when what is going on is uncomplicated enough for a human brain to reason about all the potential cases without strain
Eric S. RaymondThe only way to write complex software that won't fall on its face is to hold its global complexity down - to build it out of simple pieces connected by well-defined interfaces, so that most problems are local and you can have some hope of fixing or optimizing a part without breaking the whole
Eric S. Raymond