pyvenv - Why provide access to the system-wide python executable and standard library?
<p>When I create a virtual environment with <code>pyvenv</code>, the virtual environment's <code>python</code> executable is symlinked to the system-wide installation and consequently, I can access the system-wide standard library. 
Why is this? 
Isn't the whole point of a virtual environment to hedge against API changes in modules? 
Can't changes in the standard library break an application, too?</p>
