Its all in the hands.

This is inspired by an excellent article I came across on the Tim Hunkin website written by professor F.T. Evans.
Ever since the human race came out of the trees, we've been learning to manipulate the material world by thinking through our hands.
For instance, take a caveman looking for a way to kill that wild animal over there for dinner. The brain formulates a plan to bash it over the head with a stick, so he sets about finding and testing the right stick for the purpose using his hands to make a judgement. Tool-using such as this intimately connects our brain to our hands, and is the source of much technological progress in the human race: you think a plan in your brain, then realize it in the material world with your hands, often using tools. This continues to the present day with very sophisticated tool using.
As craftspeople in the building trades, we are well aquainted with tool-using thinking. Its a real skill, and one that is in danger of being devalued by our button-pushing society. As building trade employers will know, it is very difficult to find, or train up, potential employees with "intelligent" hands.