One opinion is that H+ is just common sense and the lack of future shock. "Typically people encountering transhumanism for the first time assume that oh these people are a bit different. What's different about them - they must love technology. It's not about loving technology. It's just that the usual yuck-reaction is missing and the ordinary philosophy of good means to good ends takes over."

• from http://www.transhumanisme.nl/yudkowsky.html

Many people think that transhumanists are "born":

• http://alt-transhumanism.ru/ - an idea that "immortality seekers" are a special breed. Transhumanists have something in them from birth and other people are extremely less likely to become ones.
• Also Yury Pichugin from CI once wrote about that

Another possibility is that they are made and you can "convert" a person to transhumanism.