It is this force that holds together the matter that forms solid bodies; holds together atoms in molecules, and electrons in atoms. This is what makes chemistry and living matter work. It is this force that operates in the neurons of our brain and governs our processing of the information on the world we perceive, and the way we think. And it’s always this force that creates the friction that stops a sliding object, that softens the landing of a parachutist, that turns electric motors and combustion engines,* or that allows us to turn on lights and listen to the radio.

