The letter ℘: name and origin? (2017)
Mathematicians’ use of obscure symbols—exemplified by the Weierstrass ℘, a stylized “p” used for an elliptic function—highlights how hard it can be for learners to even name what they’re seeing, let alone look it up. Commenters trade stories about misfiring web searches, inconsistent symbol names, and the cognitive load of fonts and scripts (Greek, Fraktur, blackboard bold) carrying semantic meaning. They point to tools like Detexify, Unicode charts, and modern AI/vision models as partial workarounds, while arguing that better symbol tables and notation maps in textbooks would make advanced mathematics far more accessible.
Difficulty of Learning Mathematical Symbols
- Many commenters struggle to read math when they can’t “say” a symbol; unfamiliar glyphs block parsing.
- Abstract squiggles (e.g., ℘, ξ, ζ) are hard to name, look up, or remember, especially from non-digital sources.
- Some recall discovering only later that familiar constructs like “dx/dt” behave algebraically, revealing how symbolic “tokens” can obscure meaning.
Tools and Methods to Identify Symbols
- Drawing-based tools like Detexify and Shapecatcher are praised for mapping sketches to LaTeX/Unicode symbols.
- Unicode utilities (e.g., command-line programs or PDFs of symbol charts) help once you can copy/paste the character.
- Vision and text LLMs are now viewed as practical “symbol lookup” tools, though results can be hit-or-miss.
Notation Conventions and Overload
- There’s appreciation for books with “tables of symbols” and dependency maps; lack of this is seen as a barrier.
- Complaints focus on:
- Overuse of single letters with font-based semantics (bold, blackboard bold, Fraktur, script).
- Ambiguous or nearly indistinguishable glyphs (e.g., nu vs v, Xi vs its conjugate with bars).
- Proliferation of stylistic variants with distinct Unicode codepoints.
- Others defend this ecosystem as a compact, time-tested shorthand that supports abstraction and reusability.
Unicode, ℘, and Historical Context
- Unicode labels ℘ as “SCRIPT CAPITAL P” (U+2118), but commenters note it is functionally a special lowercase symbol used for the Weierstrass elliptic function.
- Technical notes are cited stating the intended alias “WEIERSTRASS ELLIPTIC FUNCTION.”
- Discussion links its shape to historical German scripts (Fraktur/Sütterlin) and broader script politics, but the exact influence on notation is acknowledged as uncertain.
Comparisons to Programming Languages
- Some argue programming notation (ASCII identifiers like
sum) is more searchable and self-explanatory than mathematical symbols like Σ. - Others counter that programming is equally arcane, with its own dense shorthands and symbolic operators; restricting alphabets doesn’t guarantee clarity.