The &quot;We are all adults&quot; thing often gets brought up when discussing codes of conduct at various work places I&#x27;ve been at.  It tends to fail spectacularly.<p>The main reason is that &quot;common sense&quot; is more a matter of culture than it is &quot;sense&quot;. For most people, &quot;common sense&quot; is the thing that you don&#x27;t think about, don&#x27;t question, don&#x27;t investigate alternatives to... because it is &quot;common sense&quot;.  Probably you can see where I&#x27;m going with this.<p>&quot;Common sense&quot; is a big heading for all the things I believe strongly in, and wish that everyone agreed with me.  If someone disagrees, it practically begs ridicule because how can someone disagree with common sense?  And yet, it is also the thing we do not question.<p>&quot;Being an adult&quot; is very similar.  Adults have a code of conduct.  It is obvious.  For example you <i>don&#x27;t</i> belittle other people.  You don&#x27;t ignore to other points of view.  You don&#x27;t drink alcohol at lunch time during a work day.  You don&#x27;t show up to work late.  You don&#x27;t wear running shoes to the office.  You don&#x27;t act friendly to the cleaning staff (what if they got uppity?)  And... you see where I&#x27;m going.  <i>Somebody</i> thinks that various of these things are obviously &quot;Adult behaviour&quot;.  <i>Somebody</i> will not. And both of those people will be adults.<p>Such a code of conduct will invite unbelievable flame wars in my experience, because you will have people naively thinking that everybody thinks the same way as they do.  When they find out that it is not true they will ridicule the others for not being &quot;an adult&quot;... and the &quot;fun&quot; begins.