Everything done at the expense of other thing gains much force than if it were be done for its own purpose.
Though knowledge can be opposed to ignorance, it does not grow at its expense, since ignorance offers nothing to be overcome. Without such competition, the knower and the ignorant easily change their positions of superiority. Almost always there is a longing for ignorance and one for wisdom.
The searching for something that can oppose to knowledge should become a parallel duty to that of acquiring knowledge. And it should be done with the same rigor.
The rigor in philosophical investigation supposes a special attention to not include into the research elements that are alien to it; the condition of expressing only justified beliefs is derived from this care for rigor.
Likely, the search for the opposite of knowledge has to eliminate all is outside to it. But outside of the searching process is what stays unmoved and unquestioned. The amount of common beliefs and prejudices is also unmoved and it is not opposed at all to the knowledge, having a proper balance and stability.
Something that opposes to knowledge and being in motion is your own resistance to advance in the knowledge of things. It is in motion because it appears as a withdrawal from the ascendant trend of knowledge. Often such withdrawal takes the form of postulating immobile conceptual frames of knowledge, which are thought of as ends of knowing account.
In this way, the knowledge confined to strict conceptual frames is one that did not identify its opposite and, therefore, it is a weak knowledge. Nonetheless, the same destructive action can be performed by what resembles to a conceptual frame, as there is the variety of subject matters that constitutes the substance of the public interest.