Food in Uncertain Times

I've been following a discussion about the 5 crops (foods) that should be grown for sustainable living in uncertain times.  They are: potatoes, corn, beans, squash and eggs.  My gosh I have to say I disagree with the potatoes and corn.  I will be discussing this in greater detail on my cooking blog but from a gardening perspective you really do need a fair amount of space to grow enough potatoes