Many capitalized words disappeared. the capitalized world Soul (anima) dissapeared in favour of mind, which is a secularized term, cleared from any transcendental meaning. lower case soul reappear to mean the source of mundane feelings once the upper case version dissapeared in the upper strates of society (written books is a cultural product of the upper classes). Note the lack of overlapping. This probably means that Soul and soul were not used as sustitutives, but as these two very different meanings.
Almost the same seems to happen between capitalized Faith and trust. uncapitalized 'faith' remained very popular. probably with a metaphoric meaning in fiction writings. the other two probably were used in serious writings in their respective periods.
Capitalized Charity suffered the same decline during the XVIII century. 'charity' has declined since then. fraternity after and solidarity in modern times had become increasily popular, although is a little surprise for me how steady has been the rate of substitution.
The emphasis of the nature of things, exemplarized by the world Being and to become what one could potentially be is in a holistic way, exemplified by Virtue, has been substituted by other more defined pure supposedly objective external qualities as ideals of life. virtue were popular around the French Revolution. Freedom as one of the main purposes of Man start in the XVIII century and grows steadily until now. I guess wealth would have the same evolution:
Observe the correlation of both terms, until the XX century and the advent of the totalitarian socialisms. The fine analysis of the ups and downs would accomodate to the historical events like the layers of sediments accomodate to the geological history. note the the peak of freedom during the happy 20`s, the divergence during the great recession and the totalitarian regimes.
The rigts/duties graph show better the break of the XX century:
that inaugurate the age of Statism, understood as a period where the main subject of the political life is the relation between the State (wheter democratic autoritarian or totalitarian ) and an atomized individual who is subject of right supposedly guaranteed by the State. Duties are not mentioned under socialism because the duties should dissapear, thanks to the scientific revolutions, according with the utopical worldviews of the XX century.
On the contrary, in the XIX century, the age of liberalism, the individuals are subject of rights and duties with others individuals, where the political life is understood as a form of social contract, in analogy with the market and private contracts, while the state is subsidiary.
Seen from the XX century, the XVIII, XIX centuries look conservative, but in in these centuries there are a radical break with previous centuries based in the religious and philosophical essences like Faith, Being and Virtue. The XVIII century break also with the tradiional notions of what is to be Man and a society and what is the purpose of life. This is substituted by an agnosticism in matters of final purposes and schematic rationalizations in matters of ordinary life: Locke, Rousseau, Hobbes. These views are anachronistically consideeed now as "conservative" or "progressive", but they have a thing in common: the rejection of tradition for the shake of individual scrutiny, no matter how brigt or poor it is. The main concern is not Truth but the exercise of the right to question anything and confront it with the individual judgement, That was initiated by the protestant reformation, would end in the age of the Individualism, Statism, Mass movements, Democracy, Demagogy, Tolerance, violent revolts, ideological wars, pacifism, terrorism, genocide, globalism, Nihilism and sectarian movements where we live today.