I don’t like Mokyr’s categories of knowledge. I tend to state them as “knowledge of construction” and “knowledge of use”. Now he’s been trying to talk about the knowledge economy, so only usable knowledge is meaningful to him.
But I think this is the correct expanded hierarchy.
0) Knowledge of identity. (we are aware of it)
1) Knowledge of consequence. (what changes in state we can observe)
2) Knowledge of use. (how to put it under out control to change states)
3) Knowledge of construction. (what its made of and how its made)