# What is the name of this symbol and what is the command to display it in LaTeX? [duplicate]

Below is an image that I took of a symbol in "Logic for Philosophy" by Theodore Sider. The symbol is used to represent a function whose domain is Sentence letters of propositional logic and whose range is the set {0,1} (Called a PL-Interpretation... it basically assigns truth value to different capital letters). What is the name of this symbol and how can it be reproduced in LaTeX?

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## marked as duplicate by Heiko Oberdiek, mafp, Gonzalo Medina, Andrew Swann, cmhughesJun 18 '13 at 16:34

You can use Detexify to answer such questions, for example:

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Using Detexify you can see, that this symbol is called \mathscr{I} and you need to include \usepackage{ mathrsfs } to use it.
And an alternative name is \mathcal{I} from the calrsfs package.