This is a book that juxtaposes many opposites: poor and rich, good and evil, selflessness and selfishness, weakness and strength. The arduous week-long journey that Nell and her grandfather undertake also reflects a journey through life: with all its good and bad sides, experiences, disappointments, surprises and temptations. During the course of the story Nell shows herself to be an angel living on earth, whom everyone loves and in whose heart there is only good. She never falls into temptation like her grandfather or other "older and wiser" characters we encounter.
In stark contrast to her stands Quilp, who seems to feed exclusively on the suffering of others, especially when he initiates that suffering. Both find death towards the end of the book - again in very contrasting circumstances. While the one finds a horrible lonesome end by drowning in a dark foggy night, the other passes contentedly surrounded by people who adore her and who will always remember her and her angelic character. Is Nell a real person, or does she represent kindness, of which we readers should take something to heart?
On our way, we see a lot of early 1800s life in England too: the poignant situation in industrial towns, the poverty in London, city and village life, the wandering entertainment scene, the relationships between societal classes. The numerous characters are very Dickensian - caricaturous, but it's Dickens who's created them and he does that for a reason, so he's forgiven. The one who I wouldn't call typical is Mr, Swiveller, for his character indeed develops from just a lousy young man enjoying life to someone who feels responsible for the faith of others.
Apart from the touching and teaching story, I always admire and love the way Dickens describes some of the simplest things and which makes his books such a joy to read - I wish I had some of his talent :)