> It means having the fewest parts needed in order to accomplish your requirements.
That is exactly what "deep" means, in the terminology of this post (from Ousterhout's book A Philosophy of Software Design). Simple means "not complex" (see also Rich Hickey's talk Simple Made Easy: https://www.infoq.com/presentations/Simple-Made-Easy/), while "deep" means providing/having a lot of internally-complex functionality via a small interface. The latter is a better description of S3 (which is what you seem to be saying too) than "simple" which would mean there isn't much to it.
That is exactly what "deep" means, in the terminology of this post (from Ousterhout's book A Philosophy of Software Design). Simple means "not complex" (see also Rich Hickey's talk Simple Made Easy: https://www.infoq.com/presentations/Simple-Made-Easy/), while "deep" means providing/having a lot of internally-complex functionality via a small interface. The latter is a better description of S3 (which is what you seem to be saying too) than "simple" which would mean there isn't much to it.