The pre-eminent 19th century British ethicist, Henry Sidgwick once said:
All important ethical notions are also psychological, except perhaps the fundamental antitheses of 'good' and 'bad' and 'wrong', with which psychology, as it treats of what is and not of what ought to be, is not directly concerned (quoted in T.N. Tice and T.P. Slavens, 1983).
Sidgwick's statement can be interpreted to mean that psychology is relevant for ethics or that psychological knowledge contributes to the construction of an ethical reality. This interpretation serves as the basic impetus to this book, but Sidgwick's statement is also analyzed in detail to demonstrate why a current exposition on the relevance of psychology for ethical reality is necessary and germane.