Quote from : Pride and Prejudice Book

There is so much of gratitude or vanity in almost every attachment, that it is not safe to leave any to itself. We can all BEGIN freely--a slight preference is natural enough; but there are very few of us who have heart enough to be really in love without encouragement. In nine cases out of ten a women had better show MORE affection than she feels. Bingley likes your sister undoubtedly; but he may never do more than like her, if she does not help him on.