Why are lies dangerous?

In very simple circumstances the lie is often more harmless in regard to the maintenance of the group than under more complex conditions. Primitive man who lives in a small group ... surveys and controls the material of his life more easily and completely than does the man of higher cultures. ... the practice of his life is guided in the main by those few facts and circumstances of which his narrow angle of vision permits him to gain directly a correct view. In a richer and larger cultural life, however, existence rests on a thousand premises which a single individual cannot trace and verify to their roots at all, but must take on faith. Our modern life is based to a much larger extent than is usually realized upon the faith in the honesty of the other ... Under modern circumstances, the lie, therefore, becomes something much more devastating than it was earlier, something which questions the very foundations of out life ... modern life is a 'credit economy' in a much broader than economic sense.