The themes in Little Dorrit

Other readers have pointed out the 2 main themes of Little Dorrit, so I don’t need to write much about them. The main one is the prison theme: we have the Marshalsea prison and the Marseilles prison, London society is more or less a large prison, everyone in the book is imprisoned in one way of another—disability, constraints of social factors, or prison of the mind. 
The 2nd one is the theme of sun and shadow. The sun is already in the 1st line of the book: 

“Thirty years ago, Marseilles lay burning in the sun, one day.” (B.1, ch.1) 

Look at this line, when Arthur Clennam is about to tell William Dorrit he’s going to be released: 

“He looked steadfastly at Clennam, and, so looking at him, seemed to change into a very old haggard man. The sun was bright upon the wall beyond the window, and on the spikes at top. He slowly stretched out the hand that had been upon his heart, and pointed at the wall.” (B.1, ch.35) 

This is the day the Dorrits leave the prison: 

“There, were some who, in pure meanness of spirit, cringed and bowed before the enriched Collegian and his family; there, were others who did so really because their eyes, accustomed to the gloom of their imprisonment and poverty, could not support the light of such bright sunshine.” (B.1, ch.36) 

A quick search on Gutenberg and some calculations tell me that there are (at least) 75 words in Little Dorrit that are “sun”, “sunlight”, “sunshine”, “sunbeams”, “sunny”, “sunrise”, or “sunset”. I didn’t count “sunburnt”. 
Tom at Wuthering Expectations wrote about these themes: 
http://wutheringexpectations.blogspot.com/2012/01/dorrit-miscellaney-with-rambling.html 
Tom also wrote about the idea of the gentleman:  
http://wutheringexpectations.blogspot.com/2012/01/its-my-intent-to-be-gentleman-its-my.html 
Go read that blog post 1st and come back. 


I agree with Tom, but see it slightly differently: I see it as the theme of money and class—categorise the characters as having money, or class, or both, or neither.  
The Barnacles have both money and class, and they embody everything that Dickens hates. The book contains lots of satire of the aristocrats and the bureaucrats. 
In the Merdle family, Mr Merdle has money and Mrs Merdle has class, expressed as “manner”—she complains about his manner and he says “You supply manner, and I supply money.” (B.1, ch.33) He also says:

“If you were not an ornament to Society, and if I was not a benefactor to Society, you and I would never have come together.” (ibid.) 

In Mrs Merdle’s eyes, Fanny Dorrit has nothing—they go about in different societies. 
The marriage of Minnie Meagles and Henry Gowan is the reverse of the Merdle marriage. The Gowans have class and Mrs Gowan sees Minnie as beneath her son, but accepts the marriage because the Meagles have money and pay off Henry’s debts.  
The Dorrits, except for Amy (Little Dorrit), are the most interesting case, because for the 1st half of the book they have neither but act like they do, and put on a show of gentility. The father is delusional and in denial. The son and older sister also have pretensions and get touchy, without knowing that whilst they demand to be treated in a certain way, they themselves don’t have the manners of high class that they think they do. 
Fanny Dorrit, for example, feels humiliated about Mrs Merdle, but it is her who allows Mrs Merdle to insult her by accepting the money. 
Tip, in his self-entitlement, asks Arthur Clennam for accommodation and gets rejected and thus accuses Arthur of not treating him like a gentleman, without knowing that he’s not behaving like a gentleman. 
At the end of Book 1, however, the Dorrits come into money. I can tell that Tip, now Edward Dorrit, and Fanny, will act like they have always had money, and will be very obnoxious and intolerable, whereas Amy probably won’t change much. 
Another character in the book who also calls himself a gentleman though he isn’t, is Monsieur Rigaud, aka Lagnier, aka Blandois. 
From the 1st chapter, he insists on being seen as a gentleman, even though he’s in prison, convicted of murdering his wife. There is no evidence that he belongs to the upper class or upper middle class. 

“Mr Blandois, during this exposition, had been strictly attentive, keeping his eyes fastened on the lady, and thoughtfully stroking his moustache with his two hands. Mr Flintwinch had been a little fidgety, and now struck in.
‘There, there, there!’ said he. ‘That is quite understood, Mrs Clennam, and you have spoken piously and well. Mr Blandois, I suspect, is not of a pious cast.’
‘On the contrary, sir!’ that gentleman protested, snapping his fingers. ‘Your pardon! It’s a part of my character. I am sensitive, ardent, conscientious, and imaginative. A sensitive, ardent, conscientious, and imaginative man, Mr Flintwinch, must be that, or nothing!’
There was an inkling of suspicion in Mr Flintwinch’s face that he might be nothing, as he swaggered out of his chair (it was characteristic of this man, as it is of all men similarly marked, that whatever he did, he overdid, though it were sometimes by only a hairsbreadth), and approached to take his leave of Mrs Clennam.” (B.1, ch.30) 

What about the Clennams? They have money. I’m starting Book 2, so I don’t know what’s going to happen, but a few spoilers here and there have told me that they are going to lose money. The Dorrits get rich, the Clennams become poor. 
Let’s see.