kquote>
<p>This is the <em>left elimination rule for conjunction</em> in natural deduction, and of course the right elimation rule of conjunction is demonstrated by the <code>snd</code> function of type:</p>
<pre><code class="language-clojure">(==&gt; (and-by-all-means A B)
     B)
</code></pre>
<p>So what we reconstructed here, using only the lambda-calculus and LaTTe, is the common logical characterization of conjunction in natural deduction with its introduction and elimination rules.</p>
<p>We can go ve