How and when did Snape learn Occlumency ?

[dungrollin]

No: HPFGUIDX 116463


> Potioncat:
> I don't think we know he is an Legilimens, although there are 
> hints that he might be.  He uses that spell, with a wand while 
> teaching Harry.  But LV doesn't need a wand to do it. 
> 
> I think he knows Harry is not telling the truth during the scene 
> with the petrified cat.  Although I don't think he could get all 
> the details.  Same for the scene in GoF where he makes Harry sit 
> near his desk and threatens him with veritaserum.

Dungrollin:

I think we have more than hints, don't we?  DD says at the end of 
OotP that he's a sufficiently good legilimens to know when he's 
being lied to, when he was talking to Kreacher.  That implies to me 
that there are two kinds of legilimency.  There's the spell, the 
incantation ("Legilimens!") for which you need a wand, and which 
allows you to see the memories of the person you're attacking.  But 
there's also (presumably once you're sufficiently proficient at the 
spell) the bonus of generally knowing when you're being lied to.  
There are several mentions of Harry wondering if Snape can read 
minds, and whenever Snape suspects Harry of lying he's invariably 
right, Harry *is* lying. That's surely Legilimency of the kind that 
DD mentions at work.

Which makes me wonder about Occlumency.  Occlumency seems to have 
parallels with Legilimency, in that a sufficiently accomplished 
Occlumens can lie in casual conversation to a Legilimens and get 
away with it.  But you don't protect your self from the 
spell "Legilimens!" with "Occlumens!".  Or maybe you do, and Snape 
forgot to mention it in the lessons...  Which would explain why 
Harry wasn't getting anywhere.

Dungrollin