�S�C�������AElementary stochastic calculus with finance in view ���ݺ���

����Ten years ago I would not have dared to write a book like this�� a non-rigorous treatment of a mathematical theory. I admit that I would have been ashamed�� and I am afraid that most of my colleagues in mathematics still think like this. However�� my experience with students and practitioners convinced me that there is a strong demand for popular mathematics. I started writing this book as lecture notes in 1992 when I prepared a course on stochastic calculus for the students of the Commerce Faculty at Victoria University Wellington ��New Zealand��. Since I had failed in giving tutorials on portfolio theory and investment analysis�� I was expected to teach something I knew better. At that time�� staff members of economics and mathematics departments already discussed the use of the Black and Scholes option pricing formula�� courses on stochastic finance were offered at leading institutions such as ETH Zurich�� Columbia and Stanford�� and there was a general agreement that not only students and staff members of economics and mathematics departments�� but also practitioners in financial institutions should know more about this new topic.