Roughly speaking General Relativity is summarized with one equation but 15 or so equations are packed within it. Sorry if that's wrong, but I'm not an expert or anything. (If I could get an answer to that questions I would appreciate it to). I saw once a physicist show me a finite list of how many equations the Standard Model is composed of as an argument that it must not be the whole story seeing as GR is so simple and so elegant and is only composed of one equation. So how many equations do you have to master if you want to learn the Standard Model of particle physics. I have found this page http://blogs.discovermagazine.com/cosmicvariance/2006/11/23/thanksgiving/#.WZ_2-Xd94qI and on it I can count 15 equations.