\import{set.tex} \import{set/cons.tex} \import{set/powerset.tex} \import{set/fixpoint.tex} \import{set/product.tex} \import{topology/topological-space.tex} \import{topology/separation.tex} \import{topology/continuous.tex} \import{topology/basis.tex} \import{numbers.tex} \import{function.tex} \section{The canonical topology on $\mathbbR$} \begin{definition}\label{topological_basis_reals_eps_ball} $\topoBasisReals = \{ \epsBall{x}{\epsilon} \mid x \in \reals, \epsilon \in \realsplus\}$. \end{definition} \begin{theorem}\label{reals_as_topo_space} Suppose $\opens[\reals] = \genOpens{\topoBasisReals}{\reals}$. Then $\reals$ is a topological space. \end{theorem} \begin{proof} Omitted. \end{proof}