How does the exchange in David's innocent "third hand" incident deal with some of the central issues in The Chrysalids by John Wyndham?
'I only meant if,' I protested. I was alarmed, and too confused to explain that I had only happened to use one way of expressing a difficulty which might have been put in several ways. I was aware that the rest had stopped gaping at me, and were now looking apprehensively at my father. His expression was grim.
'You--my own son--were calling upon the Devil to give you another hand!' he accused me.
'But I wasn't. I only--'
'Be quiet, boy. Everyone in this room heard you. You'll certainly make it no better by lying.'
'Were you, or were you not, expressing dissatisfaction with the form of the body God gave you-- the form in His own image?'
' I just said if I--'
'You blasphemed, boy. You found fault with the Norm. Everybody here heard you. What have you to say to that? You know what the Norm is?'
I gave up protesting. I knew well enough that my father in his present mood would not try to understand. I muttered, parrot-like:
'"The Norm is the Image of God".'
'You do know--and yet, knowing this, you deliberately wished yourself a Mutant. That is a terrible thing, an outrageous thing. You, my son, committing blasphemy, and before his parents!' In his sternest pulpit voice, he added:
'What is a Mutant?'
'"A thing accursed in the sight of God and man",' I mumbled.
'And that is what you wished to be! What have you to say?'
With a heart-sunk certainty that it would be useless to say anything, I kept my lips shut and my eyes lowered.
'Down on your knees!' he commanded. 'Kneel and pray!'
The others all knelt, too. My father's voice rose:
'Lord, we have sinned in omission. We beg Thy forgiveness that we have not better instructed this child in Thy laws....' The prayer seemed to go booming on for a long time. After the 'Amen' there was a pause, until my father said:
'Now go to your room, and pray. Pray, you wretched boy for a forgiveness you do not deserve, but which God, in His mercy, may yet grant you. I will come to you later.'
In the night, when the anguish which had followed my father's visit was somewhat abated, I lay awake, puzzling. I had had no idea of wishing for a third hand, but even if I had...? If it was such a terrible thing just to think of having three hands, what would happen if one really had them--or anything else wrong; such as, for instance, an extra toe--?
One issue that this innocent incident deals with--innocent because David used a simple idiomatic expression to convey his difficulty in self-doctoring his wound--is what Joseph Strorm represents in The Chrysalids. Strorm is the symbol of (and in an allegorical reading, the allegorical figure of) unyielding, unthinking blind adherence to a standard or cultural ideological construct. By way of definition, a cultural ideological construct is any idea or system of ideas that establishes, supports and sustains the power structure, in this case, the Old People's adamant fight against mutations (which, immediately after the Tribulation, may have been needed and logical but may since have become stagnant and counter-productive).
Another issue that this incident deals with is the punishments given to mutants. It is brought up as David lies awake in anguish thinking about Sophy:
If it was such a terrible thing just to think of having three hands, what would happen if one really had them--or anything else wrong; such as, for instance, an extra toe--?
The issue of punishment, or, from Wyndham's perspective, unreasoning punishment, for events that occur outside of the realms of control or intent is introduced through Strorm's treatment of David and the later treatment of Sophy. It surfaces again and again throughout the story through David's aunt and baby, through the think-talkers, through Uncle Axel's protective attitudes, through David's encounter with his mutant paternal uncle. Interestingly, it also surfaces in an ironically oppositional way through the question of Angus Morton's "great-horses."
Rumours of great-horses had reached our district though none had been seen there. ... the fact that Angus was the importer ... [caused the] prejudice that he went to inspect them [with].
His doubts were confirmed at once. The moment he set eyes on the huge creatures standing twenty-six hands at the shoulder, he knew they were wrong. He ... went straight to the inspector's house with a demand that they should be destroyed as Offences.