Everyone likes rules of thumb, here&#x27;s mine the probability that you are in a bubble correlates with the ratio of opportunistic investors to craftsman investors.<p><pre><code>               &quot;opportunisitc entrepreneurs&quot;
   P(bubble) = -----------------------------
                 &quot;craftsman entrepreneurs&quot;
</code></pre>
Or more precisely craftsman(people?) entrepreneurs are more driven to change the world and have a &quot;purer&quot; motive for what they do, opportunistic entrepreneurs simply grow the number of startups similar to the ones started by the craftspeople.