Sentence:  Plato sympathizes with the desire to influence <WSD>weak-minded</WSD> people. However, rather than directly controlling the minds of such people by the power of his own will, he uses the power of his thought to construct a myth designed to control the beliefs of the <WSD>weak-minded</WSD> by appealing to their imagination. 
Meaning of the word marked with <WSD> tags:  weak-willed; easily swayed or corrupted.