Question from a newbie: Taking memories out of your head?

[justcarol67]

No: HPFGUIDX 164093

Dana wrote:
> 
> <snip> I just read the chapter of the first lesson with Snape again
and after it Snape puts the memories back. There would indeed be no
reason to put them back if there are a mere copy. I still think it is
fishy but have to re-read it again before I can make up my mind.

>
Carol responds:
I agree that the memories have been "cut" rather than "copied" in this
case (though Slughorn's may be different). I think the suggestion that
zgirnius made up thread about some shadow of a memory remaining even
when the detailed, objective memory is removed is also applicable.
IOW, even if Snape couldn't remember the details of his humiliation
because the memory is in the Pensieve (and he certainly didn't those
details to rise to the surface of his mind when he was teaching Harry
Occlumency), he would remember that the incident happened, just as
Harry would have remembered that Cho had kissed him if he could have
put that memory in a Pensieve to protect it from Snape. He would just
be protecting the objective details, the image of what happened, from
Snape's Legilimens spell. 

Snape probably doesn't have to worry about Harry using the Legilimens
spell, which he hasn't practiced and which may be beyond his skill
level, but he does have to worry, as we see later, about Harry using a
Shield Charm (Protego), even an accidental one. When the (accidental)
Protego sets up an invisible wall around Harry to protect him and his
memories from Snape's intrusion, it deflects Snape's Legilimency spell
back onto its caster, revealing random snippets of Snape's own
memories--the shouting man and cowering woman, for example.

Just by teaching Harry Occlumency, Snape was risking the exposure of
various memories, none of which he particularly wanted Harry to see,
if Harry happened to use a Protego (intentionally or not). After all,
he had told Harry to use any spell he could think of to protect
himself, and Protego is the logical defensive spell to use under the
circumstances. And while he would no doubt have preferred that Harry
not see *any* of his memories, there were a few that he particularly
wanted to protect. So I think that Snape protected himself against the
deflection of his own powerful Legilimens spell by placing that
humiliating memory and two others that were possibly even more
important (the eavesdropping incident and the "tale of deepest
remorse"?) into the Pensieve, which would store them temporarily until
it was safe to put them back inside his head.

Although the primary use of the Pensieve is presumably to "sift"
(sieve) various thoughts and memories and study them to see their
connections or implications, the use to which DD puts it in GoF, it
can also be used to temporarily store a memory that a wizard wants to
revisit to see it objectively (as opposed to the subjective,
emotion-tinged version that he would experience by simply remembering
it as a Muggle or a wizard untrained in Legilimency would). Snape,
being a Legilimens like DD, can remove memories from his own head just
as DD can, though I doubt that he habitually studies them in a
Pensieve. (He's more concerned with keeping them compartmentalized and
inaccessible to Voldemort.) I think that he agreed to teach Harry
Occlumency only if he could borrow DD's Pensieve to remove any
memories that he didn't want Harry (or LV, through Harry) to see in
case Harry succeeded in casting a Protego, and I think that DD agreed
because the idea was imminently sensible. (Neither of them anticipated
Harry's violating Snape's privacy by visiting the Pensieve.)

We saw only one of those memories, but I'm guessing that the other two
were even more sensitive, whether Snape was protecting them from Harry
or Voldemort or both. My guess is both. Snape's fury at Harry's
intrusion into the Pensieve could be explained in part by what he
might have seen if he had visited one of the other two memories
instead of that one. And that might well be a reason why DD agreed
that it was best to drop the Occlumency lessons. After all, DD
generally tells Harry only as much of the truth as Harry needs to know.

Carol, hoping that this explanation works for you as it does for me