necro81 writes: Hyperlinks are not forever. Link rot occurs when a source you've linked to no longer exists — or worse, exists in a different state than when the link was originally made. Even permalinks aren't necessarily permanent if a domain goes silent or switches ownership. According to new research from Harvard Law, some 49% of hyperlinks in Supreme Court documents no longer point to the correct original content. A second studyon link rot from Yale stresses that for the Court footnotes, citations, parenthetical asides, and historical context mean as much as the text of an opinion itself, which makes link rot a threat to future scholarship.
Mathematics deals exclusively with the relations of concepts
to each other without consideration of their relation to experience.
-- Albert Einstein