Mormon baptism for the dead is conditional - it doesn't automatically convert them, but rather the dead person gets a choice to accept that baptism or not.
But then again, while in Mormon theology the spirits are immediately sorted into paradise and "spirit prison" upon death, they can apparently communicate across the boundary between the two; and those in paradise can thus evangelize to those in prison, until they convert. So by the time they get their proxy baptism, they would presumably be convinced of its necessity.
(Although I never understood why that would even be necessary, given that by that time they already know, and thus don't have to believe...)
And yeah, Mormon theology is not what you'd expect from a religion that's so rigidly socially conservative. Between near-universal salvation and extreme Arminianism, it's really one of the most liberal among Christian denominations.
The mormon belief of being able to preach and convert after death stems from new testament teachings in Peter that Christ preached to those in "prison".
And while many Mormons take the necessity of baptism (even if after death) very literally, it is important to understand that they also believe that anyone who missed the chance to accept a posthumous baptism, will get that chance during the millennium of Christ's reign on earth, pre-judgement day.
All of that is to say, Mormons aren't frantically searching their genealogy to baptise everyone for fear their ancestors will burn in hell. There is a belief that seeking out and understanding your geneology and then setting aside time to go to the temple is beneficial to ones spirituality and well being.
But then again, while in Mormon theology the spirits are immediately sorted into paradise and "spirit prison" upon death, they can apparently communicate across the boundary between the two; and those in paradise can thus evangelize to those in prison, until they convert. So by the time they get their proxy baptism, they would presumably be convinced of its necessity.
(Although I never understood why that would even be necessary, given that by that time they already know, and thus don't have to believe...)
And yeah, Mormon theology is not what you'd expect from a religion that's so rigidly socially conservative. Between near-universal salvation and extreme Arminianism, it's really one of the most liberal among Christian denominations.