(See, for example, http://openborders.info.) Such arguments ignore our species’ lamentable xenophobic tendencies, evidenced all too clearly by the surge in popularity of far-right extremist political parties in Europe.
少数大胆的思想家倡导世界开放边界，认为这将极大促进全球GDP和平均幸福指数。（参见如http://openborders.info。）上述观点忽略了我们人类可悲的排外倾向，欧洲极右翼极端主义政党飙升的人气就是证据。