[Mesorah] Shaarei Yashar or Shaarei Yosher?

[Zev Sero via Mesorah]

On 08/24/2015 09:17 AM, Mandel, Seth via Mesorah wrote:
> There is no way it could be Yashar, and only people who do not know
> Hebrew would pronounce it like that.

Why couldn't it be "yashar"?  That's a real word, why couldn't the
sefer be called that?   I've given the reasons why I think it wasn't,
but how can you declare it impossible?

-- 
Zev Sero               I have a right to stand on my own defence, if you
zev at sero.name          intend to commit felony...if a robber meets me in
                        the street and commands me to surrender my purse,
                        I have a right to kill him without asking questions
                                               -- John Adams