Write the central idea of the poem ''To Althea ,from Prison (in 100 words).

When the poet says that stone walls and iron cages are not what makes a prison, he is saying that the real prison occurs in the mind. Those who are tossed into jail and give into the effects of solitude and dehumanizing behavior of jailers are the ones who are really imprisoned. Those who cling to dignity and maintain their humanity are never fully the victims of subjugation of their freedom and liberty. You can keep a man from experiencing liberty with his body, but the only person who truly has authority over the freedom of his mind is the man himself.