Tell-Tale Heart
I think that the main character of Edgar Allen Poe's "Tell-Tale Heart" illustrates the process of 
knowledge even though he isn't a very mentally stable person.  Near the middle of the story, he begins 
a process of knowledge when he notices that there is a noise in the room1 when he is 
talking to the police.  He slowly pays less and less attention to the officers that are in front of him and 
can only concentrate on this noise2.  He then notices that it is a faint beating 
noise3 and states that he thinks it sounds like a "watch enveloped in cotton"4.  
After this beating, which he thinks is the heart of the man that he had murdered4, gets 
to loud, he rips of the floor panels.5  After doing this, he finds that the man is still dead 
and that is wasn't the beating of the man's heart that he heard, but the beating of his own.
1) The narrator perceives that there is a noise inside the room.

2) He evaluates that noise and comes to the conclusion that it is more important that whatever the officers are saying.

3) The categoizes the noise as some sort of beating or ticking.

4) He symbolizes that noise when he compares it to the ticking of a clock wrapped in cotten. He also symbolizes when he states that it is the dead man's heart.

5) He tests these thoughts by ripping off the panels on the floor. Through these tests he finds that the noise was not the beating of the mans heart.

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