The Spirit of the Laws

Montesquieu’s comparative anatomy of regimes — the work that gave the separation of powers its modern statement and tied the character of a people’s laws to climate, commerce, religion and custom rather than to a single rational blueprint. First published in Geneva in 1748.

The list points at Book 20 specifically, not the whole work: the opening book of Part 4, on commerce. That is where Montesquieu makes the doux commerce argument — that trade inclines nations toward peace and mutual need, and softens manners, while also corroding some virtues it depends on. McCord links directly to the text of Book 20 at classicliberal.tripod.com rather than to an edition of the full book.

The entry carries a ☑️ on the source list. The page gives no legend for that mark, so it is recorded here only as “marked on the source list” — it is not known to mean read, essential, or start-here.

Why it’s on the list: It sits in the Renaissance-and-Enlightenment sub-section alongside Machiavelli, Hobbes, Locke and Burke — the stretch of the curriculum that moves from the ancients to the constitutional thinking the American founders inherited. The narrowing to Book 20 puts the emphasis on commerce rather than on constitutional design.

Where I saw it: Brendan McCord’s Philosopher-Entrepreneur Reading List, in the section on Renaissance and Enlightenment Political Thought. Shared on X on March 9, 2026 and saved to Kyle’s “Books To Read” Apple Note. The full 211-entry transcription, with the four parts and sixteen sub-sections, is on The Philosopher-Entrepreneur Reading List.

Connections

• The Philosopher-Entrepreneur Reading List — the curriculum this card came from.
• Government — the work’s subject: how regime forms differ and what sustains each.
• Capitalism — Book 20’s commerce argument is an ancestor of the liberal case for trade.
• Liberalism — separation of powers as a constitutional inheritance.