&quot;whenever you measure something, you are actually entangling with it&quot;<p>Exactly right, but there&#x27;s a little more to it than that.  <i>Because</i> you are entangling with it, all of the &quot;mysterious&quot; properties of measurement (Shroedinger&#x27;s cat and whatnot) can all be understood in terms of entanglement, and in particular, in terms of what happens when you get large systems of mutually entangled particles.