: To be precise: wikipedia *articles* (I think this is called "name space") are not allowed to have suppages, and not allowed to link to wikipedia pages which are not articles themselves. On the other hand, talk pages can have subpages and can refer to other talk pages or talk sub-pages (this is called "user space").  I discovered these rules when trying to find out why the "sources" page had been deleted. And I put links from the main talk page to "Literature" alongside of that to "Arguments". So interested *editors** can find this material. For ordinary *readers*, the article has to be self-contained.