We can only speculate on the nature of their relationship, but the most obvious theory is that Ferguson sees so much of himself in the fiercely driven firebrand, that he now shares an automatic empathy with Keane.

BBC: Keane's hell freezes over

Next up was the end-of-the-century, back-to-nature theory.

ECONOMIST: Fur and fashion

This theory says that most of the forces of nature, the objects around us and our own existence, are all down to the interaction of the Higgs with 16 other particles.

BBC: LHC upgrade to open up 'new realm of particle physics'

One theory that could be explored is that the nature of dark energy, which scientists think is causing the accelerated expansion of the universe, is different from the simplest human-calculated models.

CNN: Better 'baby picture' of universe emerges

Physicists would love to develop a way of unifying the forces of nature (electromagnetism, gravity and so on) to produce a Theory of Everything.

ECONOMIST: Particle accelerators

The story of Harold and Erica does not really illustrate a new, coherent, science-based theory of human nature.

FORBES: The Social Animal by David Brooks: A Scornful Review