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Metamath Proof Explorer

Theorem ssidd

Description: Weakening of ssid . (Contributed by BJ, 1-Sep-2022)

		Ref	Expression
	Assertion	ssidd	$⊢ φ \to A \subseteq A$

Step	Hyp	Ref	Expression
1		ssid	$⊢ A \subseteq A$
2	1	a1i	$⊢ φ \to A \subseteq A$