Superior or Inferior?

"The fact that man knows right from wrong proves his intellectual superiority to the other creatures; but the fact that he can do wrong proves his moral inferiority to any creatures that cannot." Mark Twain (1835-1910), USA

Is man superior to other animals?  Does the fact that he can make decisions and then still do wrong make him inferior?   Mark Twain was always good about giving us things to think about.  What's your opinion?