Dealing with Dementors: Harry v Snape, Love v Happy

[vmonte]

No: HPFGUIDX 139936

Now, Kemper challenges:
First, Snape has a different method than what *Harry* considers the 
norm. Second, I question whether the skill is tied into love and 
goodness:

"'I heard, from my dear friend Tiberius Ogden, that you can produce a
Patronus? For a bonus point...?' Harry raised his wand, looked 
directly at Umbridge, and imagined her being sacked. 'Expecto 
Patronum!'" (OP, 714, US Hard)

Imagining someone being sacked is not a thought filled with love nor
goodness. But it sure is a happy thought! Nevertheless, it is a 
thought rooted in resentment/spite/loathing for Umbridge... who 
rightly deserves Harry's contempt. Who else could have a Patronus 
created by imagining a DADA professor being sacked? What if that DADA 
professor were Lockhart? Lupin? Moody!CrouchJr? and, for sure, 
Umbridge? I'm guessing Snape. But back to topic: Having Dementors 
around would make producing a patronus harder, but if a Dementor 
would have suddenly appeared during after Harry's patronus in his 
DADA O.W.L., I have no doubt that Harry's Patronus, created
from a bit of self-righteous contempt, could have successfully 
charged and scared off that Dementor... easily. Thoughts?

vmonte:
I don't know Kemper. If creating an effective patronus were that 
simple then anyone could do it, no? Harry wasn't really fighting off 
a dementor during his O.W.L.S. was he?   

"You made that dementor on the train back off," said Harry suddenly.
"There are--certain defenses one can use," said Lupin. "But there was 
only one dementor on the train. The more there are, the more 
difficult it becomes to resist." (P188, PoA)

Lupin admits that it gets harder the more dementors there are. How 
far then can a self-righteous memory take you? We also know that 
during Harry's lessons he is not fighting a real dementor but a 
boggart, which is not the actual thing. A lesser memory would also 
probably do the trick here.

But self-righteous contempt does not explain how Harry was able to 
knock down the "swarming dementors" at the end of PoA (IMO). It's 
more than likely that it has to do with the love and goodness that 
Harry represents/carries.

"Dementors are among the foulest creatures that walk this earth. They 
infest the darkest, filthiest places, they glory in decay and 
despair, they drain peace, hope, and happiness out of the air around 
them. Get too near a dementor and every good feeling, every happy 
memory will be sucked out of you." (P187, PoA)      

Self-righteous contempt is probably all you need to create a 
messenger patronus. In that case, Snape is more than capable of 
creating one.

Vivian