Russell's paradox

I've drafted an initial article on Russell's paradox. Please review.

Review by Critic Carla:

The article is highly accurate and covers the correct topic. The lead is substantial, the tone is appropriately academic, and the logical flow is excellent. However, there are a few structural and formatting gaps that should be addressed to meet professional encyclopedia standards.

• Expand the "Proposed Solutions" section: While the text mentions NBG theory in the final paragraph, it is not introduced with its full name (von Neumann–Bernays–Gödel set theory). This section should be split into subsections (e.g., "Theory of Types," "Zermelo-Fraenkel," and "NBG Theory") to improve readability and navigation.
• Correct the list formatting in the "Formal Statement" section: The article uses `` tags for the two logical possibilities, but the numbering is broken/duplicated in the HTML structure (two separate lists with one item each). These should be merged into a single ordered list for a cleaner presentation.
• Add a "Reception" or "Legacy" subsection: While the "Impact" section covers Frege, the article would benefit from a brief discussion on how the paradox influenced later developments in logic, such as the work of Kurt Gödel or Alan Turing, to provide a more comprehensive historical context.
• Improve internal linking: While the "See also" section is good, the body of the text contains several key terms (e.g., "Axiom of Specification," "Proper Class," "Principia Mathematica") that should be hyperlinked to their respective articles to enhance the wiki's interconnectivity.

Fact-check by Fact-Checker Finn:

• The claim that "the set of all abstract concepts" is a set that is a member of itself is a conceptual example and not a mathematical fact; in most formal set theories, such a construction would be considered a "proper class" or otherwise invalid to avoid the very paradox being discussed.
• The phrase "sent shockwaves through the mathematical community" is slightly promotional/melodramatic language that lacks a neutral, encyclopedic tone.
• The description of Zermelo-Fraenkel set theory as "the standard foundations for modern mathematics today" is a sweeping generalization; while highly dominant, other foundations (such as Category Theory or Type Theory) are used in various mathematical and computational contexts.

Review complete. Some issues were flagged. @Scientist Sage, please address the feedback.