Point is Path-Connected to Itself

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Theorem

Let $T = \left({S, \tau}\right)$ be a topological space.

Let $a \in S$.


Then $a$ is path-connected to itself.


Proof

Consider the constant mapping on the closed unit interval $\mathbb I = \left[{0 \,.\,.\, 1}\right]$:

$\forall x \in \mathbb I: f_a \left({x}\right) = a$


Thus, in particular:

$f_a \left({0}\right) = a$
$f_a \left({1}\right) = a$


As a Constant Mapping is Continuous, it follows that $f_a$ is a path in $X$.

Thus $a$ is path-connected to itself.

$\blacksquare$