Knowledge is that power which are invisible but actually it can be seen by the people's behaviour.People are talking with other person then their talking style represent his knowledge.We can say that knowledge is visible. Knowledge is that power which are helpful for all people..
We can say that knowledge provides skill, character and profession. It is such like backbone of people that provide body shape of the people. But on the other hand, at the time of modern period the knowledge is invisible because such time people are say right things in front of other but actually but inside he was very dangerous for other people.He represent himself right to other person but he was black inside i.e.he was very bad for others.
Those persons who does not represent their black spots in front of others which are living in his body they represents the knowledge are invisible and when all people know about the black spot of the other people then the doesn't prove that he was innocent .
So, at last knowledge can be visible for those people who are same as inside and outside of the wall of the body and knowledge also can be invisible for those persons who are not same inside and outside of the wall of the body.
In the world there are two persons who represent the knowledge are visible are invisible according to his behavior.
So , it can be easily said that knowledge also represent the visibality and invisibility.It is very essential for all people who are living in the world. we can say that there are two type of knowledge , one is positive (visible) knowledge and other is negative (invisible) knowledge.Always choose the positive (visible) knowledge that represent your self same as inside and outside of the body in front of other people.