converse implication

Converse implication is the converse of material implication. Its logical connective is represented , written \Leftarrow.

Boolean converse implication is an operation which takes as input two logical truth values; it returns a value of false if and only if both its antecedent is false and its consequent is true, and true otherwise.

Visually,

\documentclass{standalone}
\usepackage{tikz}
%
\definecolor{fillcolor}{HTML}{8A5CF5}
%
\tikzset{truthy/.style n args={1}{%
    fill=#1,draw,%
    inner sep=0,minimum size=1cm}}
%
\begin{document}
\begin{tikzpicture}
	\path (-2,-2) rectangle (2,2);
	\node at (0,0.5) {Converse Implication};
	\node at (0,-0.5) {$P\Leftarrow Q$};
\end{tikzpicture}
\begin{tikzpicture}
	\node at (-1.5,0.5) {$P$};
	\node at (0.5,2.5) {$Q$};
	\node at (-1,0) {\small$1$};
	\node at (-1,1) {\small$0$};
	\node at (0,2) {\small$0$};
	\node at (1,2) {\small$1$};
    \node[truthy={fillcolor}] at (0,0) {$1$}; % bottom left
    \node[truthy={fillcolor}] at (1,0) {$1$}; % bottom right
    \node[truthy={fillcolor}] at (0,1) {$1$}; % top left
    \node[truthy={none}] at (1,1) {$0$}; % top right
\end{tikzpicture}
\hspace{1cm}
\begin{tikzpicture}
	\path (-3,-2) rectangle (3,2);
	% P
	\fill[fillcolor] (-1,0) circle (1.5);
	% not P and not Q
	\begin{scope}[even odd rule]
		\clip (-3,-2) rectangle (3,2) (-1,0) circle (1.5);
		\clip (-3,-2) rectangle (3,2) (1,0) circle (1.5);
		\fill[fillcolor] (-3,-2) rectangle (3,2);
	\end{scope}
	%
    \draw (-1,0) circle (1.5);
    \draw (1,0) circle (1.5);
    \node at (-1.25,0) {$P$};
    \node at (1.25,0) {$Q$};
\end{tikzpicture}
\end{document}

Notation

The converse implication of propositions from P to Q is can be formally written as its own logical connective PQ. Alternatively, as the converse, we may simply instead switch the antecedent and the consequent of the material implication PQ, and so PQ is equivalent to QP.

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