ith just those expressions as axioms. The (set of
theorems of the) meet of a collection of closed theories is the concept
generated by (closure of) the union of the theorem sets. The (set of
theorems of the) join of a collection of closed theories is the
intersection of the theorem sets. <br>
</p>
<table
 style="width: 600px; text-align: left; background-color: rgb(0, 0, 0);"
 border="2" cellpadding="5" cellspacing="2">
  <tbody>
    <tr>
      <td style="vertical-align: top;"><span
 style="font-family: ari