## Simple graph

### Set

context | $V,E$ … set |

definiendum | $\langle V,E,\psi\rangle \in \mathrm{it}(E,V) $ |

postulate | $\langle V,E,\psi\rangle $ … loopless graph |

postulate | $ \psi $ … injective |

### Discussion

Two vertices $\{u,v\}$ of a a simple graph are connected by at most one edge.