title: Does future always create a new thread?
body: <p>Let's say I do this:</p>
  
  <pre><code>(future
    (do-the-thing))
  </code></pre>
  
  <p>Am I guaranteed that, regardless of what <code>(do-the-thing)</code> does,</p>
  
  <ul>
  <li>an entirely new thread will be created, rather than getting one from a pool or anything like that?</li>
  <li>nothing other than <code>(do-the-thing)</code> will ever run on that new thread?</li>
  <li>once <code>(do-the-thing)</code> executes on that new thread, the thread will terminate?</li>
  </ul>
  
  <p>If not, under what circumstances would these assumptions be false?</p>