Only at the very end does a chastened Pip realize that his expectations and even his life were watched over all the while by the poor people he wanted so desperately to leave behind in his ambition for greatness. Dickens was writing a fable, with fabulous adventures and a fabulous conclusion. But the lesson of the fable holds. Dickens' lesson is not that ambition is wrong, in Pip's life or his own. It is the subtler lesson that ambition must be disciplined over and again by a sense of what we care most about as we go about our lives amid complexity and confusion.
Ambition is a passion.
It can take over and drive everything else before it, sometimes destroying those whom you love along the way. Like Pip, most of you will not escape life's exhilarating temptations. Power matters, too, if more subtly. And fame or celebrity will tug at you as well, whether you seek them or not. All of these are forms of power, I think, that is to say, command or influence over the attention of others.