The central argument of this book is that the default state of our brains, based largely on functional MRI (fMRI) scans, is being social and connected to others. When we are not doing anything, in so called idle state, our brain fMRI looks like when we are being social. And in that state of doing nothing we mostly think about other people.

Then Mr. Lieberman forces that argument, in rest of the book, to a conclusion that being social is like one of our basic needs for air, water, food and shelter.

My main criticism of this book is that his whole premise is based mainly on functional MRI scans, whose validity, for conclusions that Mr. Lieberman is drawing, is yet to be proven. It is like listening to something in translation, not knowing how faithful the translation is, and then making conclusions based on uncertain translation.

And he really does not go much into the issue of people who like to be loners, whose comfortable state is to be alone and who are distressed in social situations. How do they survive (and sometimes thrive) without the basic need of being social?

Mr. Lieberman has done a decent job of turning a dry and technical subject readable enough for most people but I feel the conclusions, especially from functional MRI studies, are overdrawn.