English
Let r be a binary relation symbol. The sentence states that r is transitive: if r(x,y) and r(y,z), then r(x,z).
Русский
Пусть r — бинарное отношение. Транзитивность: если r(x,y) и r(y,z), то r(x,z).
LaTeX
$$$\\\\forall x\\\\forall y\\\\forall z\\\\ (r(x,y) \\\\land r(y,z) \\\\Rightarrow r(x,z))$$$
Lean4
/-- The sentence indicating that a basic relation symbol is transitive. -/
protected def transitive : L.Sentence :=
∀'∀'∀'(r.boundedFormula₂ (&0) &1 ⟹ r.boundedFormula₂ (&1) &2 ⟹ r.boundedFormula₂ (&0) &2)