Social environment and moral progress / by Alfred Russel Wallace.
- Alfred Russel Wallace
- Date:
- 1913
Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Credit: Social environment and moral progress / by Alfred Russel Wallace. Source: Wellcome Collection.
157/180 page 145
![XVI] Progress Through Selection ever, they marry at twenty-nine, each suc¬ cessive generation of mothers diminishes in the proportion of 0*85. If this goes on for 108 years, the hundred mothers who marry at twenty have increased to 175, and in 216 years to 299 ; while those who marry at twenty-nine will have decreased to 61 and 38 respectively. It is therefore shown that under present social conditions the age of marriage necessary to preserve a station- ary population will be somewhere between twenty and twenty-nine. The above figures are, however, founded on special cases, and the actual facts are so complicated by the number of childless marriages, the rate of infantile mortality and other causes, that they must be taken only as establishing a law of rather rapid decrease of fertility with each year's addition to the average age of marriage of the mother. I have now, I venture to hope, estab¬ lished two important principles in relation to human progress. In the first place, I have shown that modern ideas as to the necessity of dealing directly with some of our glaring social evils, such as race degeneration and the various forms of sexual immorality, are fundamentally wrong к 145](https://iiif.wellcomecollection.org/image/b18022121_0158.JP2/full/800%2C/0/default.jpg)
