Generating equivalence relations

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Let $\sim$ be the equivalence relation generated by a relation $x\sim y$ on a non empty set X. Show that the equivalence relation always exists.

Note that I think I am supposed to show that the smallest equivalence relation which contains the set $\{$ $(x,y)$ : $x,y\in$ $\sim$ $\}$ exists.

How would i show that ? May I have hints?

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Here is the general structure of what I presume is the standard proof:

  1. Show that there is at least one equivalence relation that contains $\sim$ (most easily done by constructing one such relation).
  2. Note that because of 1., the set of all equivalence relations that contain $\sim$ is non-empty.
  3. Show that the intersection of all these equivalence relations is an equivalence relation.
  4. Show that this intersection is indeed the smallest equivalence relation that contains $\sim$.