TITLE: Why doesn't logic, math, physics etc have a symbol for "example"?
QUESTION [5 upvotes]: We have symbols for everything but there is no symbol for "example" despite examples being fundamental to achievements.
Why is there no symbol for "example" when there are symbols for everything else?
I'd like to be able to write a formula and then have a symbol that is commonly understood to represent that what is presented is an example.
Why is this not a good idea and was not introduced?
For example:
E=hf
¤: f=3Hz... if we use ¤ as symbol for an example

REPLY [5 votes]: Examples aren't in mathematics. They are tools for learning mathematics, but are exterior to mathematical systems. There couldn't be a "mathematical" symbol for it for just that reason. Granted, you could use a symbol, but it would be just a symbol that represents a word, not an acceptable character in a well-formed formula.