It is not easy to know the truth about these and similar practices, and even if one were to find out, it would be difficult to convince others; and it is just not worth the effort to try to persuade people whose heads are full of mutual suspicion, that even if they do sometimes catch sight of a molded waxen figure in a doorway or at a junction of three roads or on their parents' grave, they should ignore it every time, because they cannot be sure these things work.