Definition 4.21.4 (Meagre). Let $X$ be a topological space, then $X$ is meagre if there exists $\seq{A_n}\subset 2^{X}$ nowhere dense such that $X = \bigcup_{n \in \natp}A_{n}$.
Definition 4.21.4 (Meagre). Let $X$ be a topological space, then $X$ is meagre if there exists $\seq{A_n}\subset 2^{X}$ nowhere dense such that $X = \bigcup_{n \in \natp}A_{n}$.