Bluntschli's shrewd assessment of Raina's character allows him to enjoy her sometimes capricious playfulness without betraying his own practical nature. He is able to masterfully reign in her excessively romantic inclinations without destroying her own innately pragmatic nature. She wants her hero to be real just as much as her hero wants to show that he is real.
As such, Shaw shows how well suited they are: their relationship never descends to the farcical level Raina's and Sergius' courtship does.
As for Sergius, Louka brings out his innately practical side without sacrificing his romantic inclinations. He is free to be himself when he is in her presence. The language of their conversations is down-to-earth, practical, and sometimes, cynically honest. This is unlike Raina's and Sergius' conversations, which are tinged with emotionally charged idealisms.
Hello! You asked what is separately revealed about Raina, Bluntschli and Sergius in Act 3 of Arms And The Man.
At the beginning of the play (Act 1), Raina is engaged to Sergius, who is 'the hero of the hour' as her mother, Catherine tells her. Raina is ecstatic that her beau has so gallantly embodied all the ideals of a heroic warrior. However, she confesses her guilt to her mother that she privately doubted he would adequately manifest those heroic qualities in battle.
I wondered whether all his heroic qualities and his soldiership might not prove mere imagination when he went into a real battle.
In Act 2, we find that Sergius privately despises his own faux portrayal of the ideal soldier. He is certainly a Byronic hero, 'brooding on the perpetual failure, not only of others, but of himself, to live up to his imaginative ideals...' Although he is engaged to Raina, he flirts with Louka. He struggles with being Sergius, the romantic idealist; in fact, he tells Louka that he is half a dozen men.
What would the half dozen Sergiuses who keep popping in and out of this handsome figure of mine say if they caught us here?
Louka warns Sergius that her mistress is also doing her own bit of flirting, but this makes Sergius indignant. He grips her above the elbows furiously and accuses her of betraying her mistress and staining his honor by making him a party to her eavesdropping.
Bluntschli is a practical soldier. In Act 1, he disabuses Raina of all her romantic ideals about soldiers, war, and heroism.
There are only two sorts of soldiers: old ones and young ones. I've served fourteen years: half of your fellows never smelt powder before.
He tells her that Sergius' charge wasn't all that it was rumored to have been.
And there was Don Quixote flourishing like a drum major, thinking he'd done the cleverest thing ever known, whereas he ought to be courtmartialled for it. Of all the fools ever let loose on a field of battle, that man must be the very maddest. He and his regiment simply committed suicide—only the pistol missed fire, that's all.
What is revealed in Act 3
This sets the stage for Act 3 when it is revealed that Raina's frequent over- the-top posturing is all an act.
Bluntschli knows that Raina isn't really sorry for the two lies she tells. He playfully teases her. Raina finds herself falling in love with this practical soldier who sees through her youthful pretenses and yet, loves her all the same. Sergius also comes to realize that he and Raina would never be happy together as both of them are too busy deluding each other and pretending to be something they are not. Sergius is more suited to the plain-speaking Louka, just as the pragmatic Bluntschli is more suited to the temperamental Raina. When it is revealed that Bluntschli's father has died and has left to Bluntschli many big hotels to look after, Major Petkoff and his wife, Catherine's reservations about Bluntschli are disarmed. So, you can see that Shaw's play eventually pairs the right couples together.
What is interesting about the revelations in Act 3: Sergius shows he has a practical side and Bluntschli likewise shows he has a romantic side.
SERGIUS (commandingly). It means that you love me, and that I have had you here in my arms, and will perhaps have you there again. Whether that is an insult I neither know nor care: take it as you please. But (vehemently) I will not be a coward and a trifler. If I choose to love you, I dare marry you, in spite of all Bulgaria. If these hands ever touch you again, they shall touch my affianced bride.
BLUNTSCHLI. I won't take that answer. I appealed to you as a fugitive, a beggar, and a starving man. You accepted me. You gave me your hand to kiss, your bed to sleep in, and your roof to shelter me—