The Great Unmarried is a 1915 book by British journalist Walter M. Gallichan which is notable for being one of the earliest works of the modern era that took seriously the issue of involuntary celibacy. While much of the book is concerned with examining the causes of celibacy in general (in terms of being unmarried), the author does also devote substantial portions of the book to the issue of involuntarily celibacy. Various reasons are offered for the existence of this circumstance, the chief reasons in Gallichan's eye being economic problems (poor wages and economic centralization leading to intense competition in the professional fields), the pursuit of unattached sexual hedonism, cynical views of love and marriage, and what he perceived as an increasing state of social disharmony between the sexes.
Gallichan seems to consistently portray the circumstance as an issue primarily facing the women of the time, in his view, being largely caused by urbanization (in particular, the immigration of male workers to the cities) and many young men refusing or being unable to bear the financial cost of marriage. He also describes changes in social attitudes such as: "Sexphobia, misogyny, misogamy, or misandry, anaesthesia and other morbid phenomena of effete civilisation [..]" as being other contributing factors to widespread celibacy.
He describes the social ills caused by involuntary celibacy as (among other things) an increase in crime among celibate men (he cites a study that shows that unmarried men commit crime at double the rates of married men, which has been also been borne out by more modern research), involuntarily celibate men withdrawing from contributing to society ("being unsocial against their will"), falling birth rates, and an overall decrease in social cohesion and stability.
After briefly considering the legalization of polygamy as a solution to involuntary celibacy in women (soon to be exacerbated, as he warns, by the change in the gender ratio due to a decimation of an entire generation of young men in the First World War), he proposes the implementation of economic incentives to marry (such as tax breaks for the married), disincentives towards singlehood (such as bachelor taxes), increasing the minimum wage substantially, the social encouragement of marriage as a transcendent social ideal to be praised and aspired to by all, and the shaming and vituperation of what he calls "pseudo-celibacy" (promiscuity outside of marriage) as possible solutions to involuntary celibacy in both sexes.
It is quite possible that Gallichan's eugenicist views influenced the policy positions he advances in this book, as there was a tendency in the British eugenicist movement at the time to see the First World War as a potential 'dysgenic crisis', as they claimed it would lead to the death of many of the best, bravest and brightest men of the nation without issue, thus they were seeking to encourage soldiers (particularly the upper class ones) to get married and reproduce quickly, before they participated in the war.