> For the complete documentation index, see [llms.txt](https://en.chanyuan8.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://en.chanyuan8.org/lifes-wisdom/the-utility-cannot-be-seen-and-the-visible-cannot-be-used.md).

# The Utility Cannot Be Seen and the Visible Cannot Be Used