the dual nature of man, Henry Jekyll begins experimenting and creates a potion and drinks it, willingly risking his life.

Dr. Jekyll believes that he has succeeded in separating the dual nature of man, the good from the evil.  So when he sees Mr. Hyde, he is thrilled, even though Hyde is hideous looking and much smaller in stature.

With Hyde released, and Jekyll carefully hidden beneath, Mr. Hyde is set free to be wild and violent without consequences. His vicious nature released, Dr. Jekyll is able to indulge in his dark passions without shame or guilt.  He is pleased with the arrangement, as Mr. Hyde, Jekyll is animalistic in nature, but he bears no responsibility as Dr. Jekyll.

"Jekyll has a mixed response to his alter ego. When he drinks the potion and transforms into Hyde he at first admits, "I felt younger, lighter, happier in body; within I was conscious of a heady recklessness, a current of disordered sensual images running like a millrace in my fancy ... an unknown but not an innocent freedom of the soul. I knew myself at the first breath of this new life, to be more wicked, tenfold more wicked, sold a slave to my original evil;"

Dr. Jekyll believes that he needs Mr. Hyde in order to live a good and pure life.  He is able to absolve himself of temptations and desires, exercising them as Mr. Hyde so as Dr. Jekyll, his behavior is impecable, beyond reproach, he is civil, polite, upright and law abiding.

Dr. Jekyll does not repudiate his kinship with his alter ego Mr. Hyde. He seems to have a certain feeling of affection for this other individual because he recognizes him as a kindred spirit. This is not uncommon in human relations. A man who is honorable, civilized, public-spirited and law-abiding might be attracted to another man who is entirely different, who rejects conventional morality and lives to please himself. This kind of hedonistic, irresponsible man can lead an otherwise sober, industrious and trustworthy man astray, and even eventually lead that man to his utter ruin. The same thing can happen to women who are led astray by men or by other women.

In Shakespeare's Julius Caesar, the greedy, crafty, selfish, and miserly Cassius says to himself after his interview with the noble Brutus:

Well, Brutus, thou are noble; yet I see

Thy honorable mettle may be wrought

From that it is disposed. Therefore it is meet

That noble minds keep ever with their likes;

For who so firm that cannot be seduced. (I.3)

Dr. Jekyll may be naive, like Brutus, or schemeing, like Cassius. They are easy to victimize by inferior men. Both come to tragic ends.

At first, Dr. Jekyll is excited when he changes into his alter ego. "I felt younger; lighter; happier in body; within I was conscious of a heady recklessness,..." Jekyll feels a sense of freedom from his transformation, knowing that Hyde represents a part of himself. "This too was myself. It seemed natural and human. In my eyes it bore a lovelier image of the spirit, it seemed more express and single, than the imperfect and divided countenance I had been hitherto accustomed to call mine." Later, however, Dr. Jekyll realizes the evil of Mr. Hyde, noticing his smaller stature when he turns into Hyde. As Dr. Jekyll tries to control Mr. Hyde's corrupt and violent acts, Mr. Hyde gains strength, expressed by the merciless and fatal beating of Carew. Hyde enjoys the murder, displaying that "in the hands of Edward Hyde [his pleasures] began to turn toward the monstrous" reflecting Hyde's "vicarious depravity" in carrying out his crime. The only alternative left to Dr. Jekyll is his suicide.