Throughout the book, how did Charlie change? What were his personality and relationships like at each point in his growth process?

At the beginning of the story Charlie was mentally
handicapped and diagnosed with an IQ of 68. He was 32.

For
a man with mental retardation (as explained in the story), he was incredibly motivated,
making sure he worked hard at a Special university and making tasks to be selected for a
surgery which would triple his IQ.

After the surgery, the
first sign you see is that he is operating complex machines, and his IQ begins to
increase. Most importantly, he beat Algernon in completing a maze: Algernon is a rat who
underwent the same operation as a test variable.

Yet when
you put into perspective that Charlie went from two completely different sides of life
(from mentally challenged to genius) in just months, you can imagine the changes that
impacted his personality.

First of all, he would see people
for who they really were. He understood now all the digs that were thrown at him in the
beginning, and the double entendre of many jokes. He changed, because he wanted
desperately to be taken seriously. In a way, he shun everyone who was one his friend so
that he could eradicate that part of his life.

Equally, he
fell in love. When he did, he overanalyzed and over complicated things because his mind
would work so fast and with such complexity that he was now losing friends, and his
attitude continued to change.

When he realized the mistake
in the hypothesis that would contribute to his increase in IQ, his anger was not just
directed at the doctors, but at himself, at the society who laughed at him once, and at
all of those whom he once loved.

As his condition
deteriorated again, he came back to being a simple man, almost childish, still in pain
for what was gone, but most importantly, he was returned to a state of innocence that
begged for the mercy of Algernon, rather than for his own.