There are certain truths which stand out so openly on the roadsides of life, as it were, that every passer-by may see them. Yet, because of their obviousness, the general run of people disregard such truths or at least they do not make them the object of any concious knowledge. People are so bliend to some of the simplest facts in everyday life that they are highly surprised when somebody calls attention to what everybody ought to know.