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How did Gottfried Wilhelm Leibniz distinguish truths of reason from truths of fact?

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Engraved portrait of Gottfried Wilhelm von Leibniz with long curly hair, wearing a buttoned coat and cravat, facing forward. — Gottfried Wilhelm Leibniz German philosopher and mathematician Gottfried Wilhelm Leibniz, engraving, c. 1701.

Gottfried Wilhelm Leibniz distinguished between truths of reason and truths of fact based on their necessity and the principles that govern them.1

Truths of Reason: These are necessary propositions, such as those found in logic and mathematics, which hold true in all possible worlds. Their nonexistence would involve a contradiction, as they are governed by the principle of contradiction, which states that a proposition and its negation cannot both be true. These truths are often considered analytic, meaning they are knowable a priori and their truth is guaranteed by the meanings of the concepts involved.1234
Truths of Fact: These are contingent propositions that hold true only in some possible worlds, including the actual world. Their existence is not logically necessary and depends on God’s free choice. Consequently, they are governed by the principle of sufficient reason, which asserts that there must be an adequate reason to account for why something exists or is the case rather than not.12

Leibniz’s distinction highlights his rationalist approach, contrasting the indubitable, necessary nature of logical truths with the contingent nature of empirical facts.1