Good point: is our authoritarian society going to demand a fourth law?<p><pre><code>    1. A robot may not injure a human being or, through inaction,
       allow a human being to come to harm.
    2. A robot must obey the orders given it by the government, except
       where such orders would conflict with the First Law.
    3. A robot must obey the orders given it by non-government human
       beings except where such orders would conflict with the First or
       Second Laws.
    4. A robot must protect its own existence as long as such
       protection does not conflict with the First, Second, or Third
       Laws.</code></pre>