"Had I approached my discovery in a more noble spirit, had I risked the experiment while under the empire of generous or pious aspirations, all must have been otherwise, and from these agonies of death and birth, I had come forth an angel instead of a fiend."
What would Jekyll have done differently under nobler intentions? He would have attempted both of the goals he began with:
"If each [side], I told myself, could be housed in separate identities, life would be relieved of all that was unbearable; the unjust might go his way, delivered from the aspirations and remorse of his more upright twin; and the just could walk steadfastly and securely on his upward path, doing the good things in which he found his pleasure, and no longer exposed to disgrace and penitence by the hands of this extraneous evil."
Jekyll succeeded in his first goal: silencing the "just" superego so that the "unjust" id could do what it wanted with no remorse. But he never mentions even attempting his supposed second goal: silencing the id so that the superego is "no longer exposed to disgrace and penitence by the hands of this extraneous evil." No doubt, had he attempted such a thing, he would have found it completely impossible to suppress evil as easily as his drugs could release it, but he apparently never pursued such a route. Why? Because Evil Feels Good, and he was content to use his first discovery to let himself savor the joys of depravity with no remorse or risk of discovery.
Had Henry Jekyll admitted this in his explanation, of course, he wouldn't be the Hypocrite Stevenson so rightly declared he was.
Mr. Hyde Has Bad Posture
Those unfortunate enough to encounter Mr. Hyde in person but fortunate enough to live to tell the tale describe him as giving the impression of being deformed, but without any actual, identifiable deformity being visible. Normally this is interpreted as them somehow "sensing" the fact that Hyde is pure evil
, but what if that's not it?
As You Know, 90% of communication is non-verbal, and the way someone carries themselves can have just as strong an impact on how people perceive them when they see them as anything about their actual appearance, if not even stronger. Perhaps Hyde is subconsciously broadcasting his villainy through the world via disgustingly terrible posture.
Having radically different body language than Dr. Jekyll may also have played some role in why no one recognized him.
The story is a metaphor for the consequences of alcoholism
Jekyll is normally mild-mannered and submissive, but after drinking a serum, transforms into a violently abusive monster. Despite knowing the consequences of doing so, Jekyll continues to compulsively drink the serum and transform into Hyde. This ultimately destroys his life.