Varför gav Lucius Tom Riddles dagbok till Ginny?

Professor Dumbledore ger sin gissning till detta i Harry Potter och Half-Blood Prince kapitel 23.

[Harry:] ‘But I thought he meant Lucius Malfoy to smuggle it [the diary] into Hogwarts?’

[Professor Dumbledore:] ‘Yes he did, years ago, when he was sure he would be able to create more Horcruxes, but still Lucius was supposed to wait for Voldemort's say-so, and he never received it, for Voldemort vanished shortly after giving him the diary. No doubt he thought that Lucius would not dare do anything with the Horcrux other than guard it carefully, but he was counting too much upon Lucius's fear of a master who had been gone for years and whom Lucius believed dead. Of course, Lucius did not know what the diary really was. I understand that Voldemort had told him the diary would cause the Chamber of Secrets to reopen, because it was cleverly enchanted. Had Lucius known he held a portion of his master's soul in his hands he would undoubtedly have treated it with more reverence – but instead he went ahead and carried out the old plan for his own ends: by planting the diary upon Arthur Weasley's daughter, he hoped to discredit Arthur, have me thrown out of Hogwarts and get rid of a highly incriminating object in one stroke. […]’

Som Jason Baker påpekar i sitt svar, förklarar professor Dumbledore lite mer av Lucius motivation, speciellt om att diskreditera Weasleys, i Secrets of Secrets , på ett tunt förtäckt hypotetiskt sätt, eftersom han har inte tillräckligt med bevis för att bevisa Lucius skuld.

Mr Malfoy went even paler than usual, but his eyes were still slits of fury.

‘So – have you stopped the attacks yet?’ he sneered. ‘Have you caught the culprit?’

‘We have,’ said Dumbledore, with a smile.

‘Well?’ said Mr Malfoy sharply. ‘Who is it?’

‘The same person as last time, Lucius,’ said Dumbledore. ‘But this time, Lord Voldemort was acting through somebody else. By means of this diary.’

He held up the small black book with the large hole through the centre, watching Mr Malfoy closely. Harry, however, was watching Dobby.

The elf was doing something very odd. His great eyes fixed meaningfully on Harry, he kept pointing at the diary, then at Mr Malfoy, and then hitting himself hard on the head with his fist.

‘I see …’ said Mr Malfoy slowly to Dumbledore.

‘A clever plan,’ said Dumbledore in a level voice, still staring Mr Malfoy straight in the eye. ‘Because if Harry here –’ Mr Malfoy shot Harry a swift, sharp look, ‘and his friend Ron hadn't discovered this book, why, – Ginny Weasley might have taken all the blame. No one would ever have been able to prove she hadn't acted of her own free will …’

Mr Malfoy said nothing. His face was suddenly mask-like.

‘And imagine,’ Dumbledore went on, ‘what might have happened then … The Weasleys are one of our most prominent pure-blood families. Imagine the effect on Arthur Weasley and his Muggle Protection Act, if his own daughter was discovered attacking and killing Muggle-borns. Very fortunate the diary was discovered, and Riddle's memories wiped from it. Who knows what the consequences might have been otherwise …’

Så den mörka Herren instruerade inte Lucius att förfoga över dagboken, men han avslöjade slarvigt bara den felaktiga informationen till honom att Lucius gick efter sitt eget huvud medan den mörka herren föll.

Vi vet inte, men Dumbledore spekulerar på att det var tänkt att skämma Arthur och döda sin lag som skyddar Muggles från människor som Lucius Malfoy. Med tanke på hur Lucius reagerar på Dumbledores teori var han förmodligen mest korrekt:

"A clever plan," said Dumbledore in a level voice, still staring Mr. Malfoy straight in the eye. "Because if Harry here —" Mr. Malfoy shot Harry a swift, sharp look "and his friend Ron hadn't discovered this book, why — Ginny Weasley might have taken all the blame. No one would ever have been able to prove she hadn't acted of her own free will..."

Mr. Malfoy said nothing. His face was suddenly masklike.

"And imagine," Dumbledore went on, "what might have happened then... The Weasleys are one of our most prominent pure-blood families. Imagine the effect on Arthur Weasley and his Muggle Protection Act, if his own daughter was discovered attacking and — killing Muggleborns... Very fortunate the diary was discovered, and Riddle's memories wiped from it. Who knows what the consequences might have been otherwise..."

Mr. Malfoy forced himself to speak.

"Very fortunate," he said stiffly.

Chamber of Secrets Chapter 18: "Dobby's Reward"

Anledningen till att Lucius gav Riddles Dagbok, något som Voldemort hade anförtrott honom att hålla sig tryggt, till en ung Ginny Weasley förklaras här:

Lucius plants Tom Riddle's diary in Ginny Weasley's potions cauldron while she is shopping for school supplies at Flourish & Blotts, in a plot to use her to reopen the Chamber of Secrets, which would lead to attacks on Muggle-born students. Lucius knows the diary is cleverly enchanted, but is not aware that it is a horcrux containing a part of Voldemort's soul. Lucius intends to use the opening of the Chamber of Secrets by Ginny to discredit her father, Arthur Weasley, and Dumbledore.

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