Poe and Life Science

Based on the way Poe presents the body and mind, what is his view on the connection between the two?

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In "The Fall of the House of Usher" there seems to be a notion from Poe that one should never sever the tie between the physical and the psychological. Roderick seems to portray a being who possesses a hypertrophied mind while his body is very sickly. His twin sister Madeline however, seems to solely embody the physical as she barely speaks, and even in death her cheeks remain rosy as if she were alive. Roderick's effort to kill his sister, and therefore the physical aspect of himself, results in a disastrous event that ultimately destroys his own self (the psychological aspect) also. This points to a theme that the mind and body cannot be separated by force without catastrophic consequences.

In "The Facts in the Case of M. Valdemar" the mind and body are forced to remain together post mortem. At first, the mind seems to be content separated from the pain of the body, but the mind soon finds unrest when the it realizes that the body is dead. This furthers the theme of  connection between body and mind: they cannot be forced together just as they cannot be forced apart.