ckquote class="alectryon-goal"><div class="goal-hyps"><span><var>p, q, r</var><span class="hyp-type"><b>: </b><span><span class="kt">Prop</span></span></span></span><br></div><label class="goal-separator" for="literate-lean3-lean-chk6"><hr></label><div class="goal-conclusion">q <span class="bp">‚àß</span> p <span class="bp">‚Üí</span> p <span class="bp">‚àß</span> q</div></blockquote></div></div></div></small><span class="alectryon-wsp"> </span></span><span class="alectryon-sentence"><input clas