You either know what you are doing, or you do not, and in the world of ideas ordinary minds do not – and do not acknowledge they do not.
With physical skills, you clearly possess them, or you do not. You can either, walk a tightrope, fly a plane, perform surgery, or you cannot, and no sane mind deludes itself, but in the intangible world of symbols the mind normally makes no such clear cut distinction.
Several features in the mind of man limit to distinguish him from other earthly creatures. Most of them relating to his alteration of the physical environment, to more efficiently suit his needs and desires (a capacity totally dependent on his ability to manipulate symbols in his brain which he can later apply to material conditions). The feature that his mind finds most captivating about itself IS simply its ability to play with symbols.
A prisoner in solitary confinement will trade away his meal to whoever delivered it, in exchange for a scrap of conversation. The worst punishment known to man is the deprivation of symbolic stimuli, which indeed can ultimately do as much damage to his nervous system as lack of food will to his digestive one.
When you consider the amount of technology (things that do not naturally grow from the ground) with which your life is surrounded, the importance of the mind’s symbolic manipulations put into tangible practice is obvious. When you look at the large part that culture plays in men’s lives, you are also seeing symbol-weaving at work, but in this instance – NOT so obviously.