Mathematical Symbol Fight
Mathematical Symbol Fight
[A chart is shown with 30 different symbols arranged above a line with arrows in both ends and with 17 ticks between the arrow heads. The symbols are mostly in two rows, but the first two symbols from the left do not have another symbol above them, and towards the right there are a segment with three rows of symbols. Above the symbols there is a heading and a subheading. And beneath those there is a long arrow pointing right with a label above it.] Mathematical Symbols By how useful they would be in a fight More useful ℝ     ∅ > ∝ π + Ψ ~ ⇒ ⋅ Γ √ ∮ ∫ ⇀ θ ∞ ∪ ∈ ∀ ∂ ≠ # Δ ζ ℵ ρ → ⊥ ––
[Below the double arrow line are eight characters that fight each other in groups of two by  using some of the symbols shown above them as weapons. They have chosen symbols that are almost above them in the chart.] [Megan is awkwardly handling a giant "ℝ" holding it up against White Hat who is holding a "θ" (or "∅"?) with both hands, as a shield.] [Cueball is holding an "∈" in both hands, with its "tines" pointed towards Blondie, who is swatting at him with a "#".] [Ponytail is leaping at Danish, swinging a " ρ " like an axe, while Danish is leaning back and thrusting a "→" back at her.] [Black Hat is swinging a long "√" like a polearm at Hairy, who is holding a long "⎯" defensively.]

This comic imagines which mathematical symbols would be good in a fight if they were made corporeal in two (or three) dimensions.
Generally, objects with longer reach and pointier ends wound up on the right ("more useful") side of the scale, and symbols with less reach and more curves wound towards the left ("less useful") side. A straight line is farthest to the "more dangerous" side; however, the straight line does not appear to be any thicker or thinner, or pointier, than any of the other lines that would make it more "useful" (It should be noted that this chart seems to fall afoul of what Eliezer Yudkowsky (who also wrote HPMoR) calls the intent to kill : that humans tend to define "winning a fight" and "useful" as causing some form of bodily harm on their opponent despite survival and purely defensive strategies being an equally valid goals.).
Below the chart, with the symbols listed in order of usefulness, eight characters wield eight of the symbols. See the table below for the meaning of each symbol.
The comic invokes surreal humour by suggesting that mathematical symbols could be handled as physical objects in the real world. Another component of the humor is the implication that it is useful to prepare to use mathematical symbols in a fight, even though mathematicians, who use mathematical symbols, usually do not conduct their debates violently (though some stories suggest that Hippasus was killed by his fellow Pythagoreans for his proof that irrational numbers exist), and even if they did, they wouldn't use large reproductions of their symbols as weapons.
The title text refers to a Treble clef , which is not a mathematical symbol but rather a musical symbol . The note of concern in the text suggests musical symbols may be viewed in such fights as exotic or especially dangerous. See also the last entry in the table below.
[A chart is shown with 30 different symbols arranged above a line with arrows in both ends and with 17 ticks between the arrow heads. The symbols are mostly in two rows, but the first two symbols from the left do not have another symbol above them, and towards the right there are a segment with three rows of symbols. Above the symbols there is a heading and a subheading. And beneath those there is a long arrow pointing right with a label above it.] Mathematical Symbols By how useful they would be in a fight More useful ℝ     ∅ > ∝ π + Ψ ~ ⇒ ⋅ Γ √ ∮ ∫ ⇀ θ ∞ ∪ ∈ ∀ ∂ ≠ # Δ ζ ℵ ρ → ⊥ ––
[Below the double arrow line are eight characters that fight each other in groups of two by  using some of the symbols shown above them as weapons. They have chosen symbols that are almost above them in the chart.] [Megan is awkwardly handling a giant "ℝ" holding it up against White Hat who is holding a "θ" (or "∅"?) with both hands, as a shield.] [Cueball is holding an "∈" in both hands, with its "tines" pointed towards Blondie, who is swatting at him with a "#".] [Ponytail is leaping at Danish, swinging a " ρ " like an axe, while Danish is leaning back and thrusting a "→" back at her.] [Black Hat is swinging a long "√" like a polearm at Hairy, who is holding a long "⎯" defensively.]
