theorem instLegalRuleAtToParent
theorem instLegalRuleAtToParent: ∀ (x t : Type) [LegalRule.At x t], GenericallyDependentContinuant.At x t
theorem instLegalRuleAtToParent
theorem instLegalRuleAtToParent: ∀ (x t : Type) [LegalRule.At x t], GenericallyDependentContinuant.At x t