I am indebted to you for the communication of the Prospectus of a work embracing the history of civilised man, political & moral, from the great change produced in his condition by the extension of the feudal system over Europe thro’ all the successive effects of the revival of letters, the invention of printing, that of the compass, the enlargement of science, & the revolutionary spirit, religious & civil, generated by that. it presents a vast Anatomy of fact and reflection, which if duly filled up would offer to the human mind a wonderful mass for contemplation. your letter does not ascertain whether the work is already executed, or only meditated: but it excites a great desire to see it compleated, and a confidence that the author of the Analysis is best able to develope the profound views, there only sketched. it would be a library in itself, and, to our country, particularly desirable and valuable, if executed in the genuine republican principles of our constitution. the only orthodox object of the institution of government is to secure the greatest degree of happiness possible to the general mass of those associated under it. the events which this work proposes to embrace will establish the fact that unless that mass retains a sufficient controul over those entrusted with the powers of their government, these will be perverted to their own oppression, and to the perpetuation of wealth & power in the individuals, & their families, selected for the trust. whether our constitution has hit on the exact degree of controul necessary, is yet under experiment; and it is a most encouraging reflection that, distance & other difficulties securing us, against the brigand governments of Europe, in the safe enjoiment of our farms and firesides, the experiment stands a better chance of being satisfactorily made here than on any occasion yet presented by history. to promote therefore unanimity and perseverance in this great enterprise, to disdain despair, encourage trial, & nourish hope are the worthiest objects of every political & philanthropic work: and that this would be the necessary result of that which you have delineated, the facts it will review, and the just reflections arising out of them will sufficiently ensure. I hope therefore that it is not in petto merely, but already compleated; and that my fellow citizens, warned in it of the rocks and shoals on which other political associations have been wrecked, will be able to direct theirs with a better knolege of the dangers in it’s way.

The enlargement of your observations on the subjects of natural history, alluded to in your letter, cannot fail to add to our lights respecting them, & will therefore ever be a welcome present to every friend of science. Accept, I pray you the assurance of my great esteem and respect.

Th: Jefferson