Truth is in the eye of the beholder and although your truth may be different from another's, neither is any less valid. If negativity is sent out, then it will return to the sender three times as strong. This too applies to positive energy. It's a pretty good incentive for doing only positive spiritual work. This law includes yourself.
Pagans believe that doing harm to oneself or to others in unacceptable.
When doing any type of spell for another person, the Harm Ye None Law goes into effect. Even for something as positive as a healing spell. You must always ask permission before attempting something of that magnitude. It would be doing harm to another individual to change their beliefs. If they are not attracted to you in the first place, then doing a spell to change them is wrong.