Example 1

Tag 03T5, permanent. Cite it as [Bourbaki, Tag 03T5].

Theory of Sets, chapter III, § 3. Equipotent sets. Cardinals

$\mathrm{Card}(\emptyset)$ is denoted by 0. Since the only set equipotent to $\emptyset$ is $\emptyset$ (Chapter II, § 3, nos. 1 and 4), we have $0 = \mathrm{Card}(\emptyset) = \emptyset$ .

Bourbaki sets the proof directly after the statement, and the corpus does not separate them, so what is above is the statement and its proof together.

Cited by

Nothing.

Cites

Chapter II, § 3, nos. 1