on</td><td>&nbsp;&nbsp;&nbsp;</td><td align="right">&phi;&nbsp;&#8896;&nbsp;&psi; or &#8896;(&phi;&nbsp;&psi;)</td><td>&nbsp;&nbsp;&nbsp;</td><td><span style="font-family: courier new,courier,monospace;">(and&nbsp;P&nbsp;Q)</span></td></tr>
<tr class="middle"><td align="right">disjunction</td><td>&nbsp;&nbsp;&nbsp;</td><td align="right">&phi;&nbsp;&#8897;&nbsp;&psi; or &#8897;(&phi;&nbsp;&psi;)</td><td>&nbsp;&nbsp;&nbsp;</td><td><span style="font-family: courier new,courier,monospace;">(or&nbsp;P&nbsp;Q)</s