- http://plato.stanford.edu/
- http://www.iep.utm.edu/
- http://www.joshdmay.com/teaching/philosophy-help/
- http://www.philosophypages.com/ph/index.htm
- http://www.etsu.edu/cas/philosophy/whatis.aspx
- http://www.fredonia.edu/philosophy/help.asp
- http://www.sparknotes.com/philosophy/republic/context.html
- http://philpapers.org/
- http://consc.net/people.html
- http://www.nyu.edu/gsas/dept/philo/faculty/papers/