-style: italic;">clo</span>
: <span style="font-family: arial; font-weight: bold;">Theory</span> &#8594;
<span style="font-family: arial; font-weight: bold;">Closed
Theory</span> maps the theory context onto the closed theory context.
This is illustrated by the association of the theory <span
 style="font-style: italic; font-weight: bold;">T</span><small><sub>0</sub></small>
to its closure <span style="font-family: arial; font-style: italic;">clo</span>(<span
 style="font-style: italic; font-weight: bold;">