Information will not be pushed to the user unless they intentionally ask for it. Mercury’s intention-as-context architecture vaccinates the user against the unintentional consumption of information.
To the extent that the web has been difficult to kill, it is because it is evolvable. The web started as a way for scientists to share papers, and then evolved into new niches, including e-commerce, wikis, flash games, blogs, web apps, streaming video, social media, office suites, chat apps, design tools... It keeps finding new fits, and changing... See more
The product designer's task is to create a new f(). The designer doesn't get to define x: that's empirical. And they don't get to dictate y either. A given y is only a worthwhile target if it's worth paying for in the eyes of the user — also empirical. That means x and y are requirements for f(). They are fixed, f() is variable.