The secret of a great success ...

The secret of a great success for which you are at a loss to account is a crime that has never been found out, because it was properly executed.
The secret of a great success for which you are at a loss to account is a crime that has never been found out, because it was properly executed.

Quotes from the same author

When you doubt your power, you give power to your doubt.
The smallest flower is a thought, a life answering to some feature of the Great Whole, of whom they have a persistent intuition.
Physically, a man is a man for a much longer time than a woman is a woman.
He has great tranquility of heart who cares neither for the praises nor the fault-finding of men.
A mother's happiness is like a beacon, lighting up the future but reflected also on the past in the guise of fond memories.