"As an advocate of birth control I wish ... to point out that the unbalance between the birth rate of the 'unfit' and the 'fit,' admittedly the greatest present menace to civilization, can never be rectified by the inauguration of a cradle competition between these two classes. In this matter, the example of the inferior classes, the fertility of the feeble-minded, the mentally defective, the poverty-stricken classes, should not be held up for emulation.... On the contrary, the most urgent problem today is how to limit and discourage the over-fertility of the mentally and physically defective."