French revolutionist, terrorist, police chief, and politician; Count Pierre-François Réal (1757 — 1834) published anonymously in 1835: Indiscrétions 1798-1830: Souvenirs anecdotiques et politiques tirés du portefeuille d'un fonctionnaire de l'Empire. Below is a an English translation of an extract from the book's introduction. His original can be read here.
I have known, and I now know, many historians: they have all honourable characters, and are generally esteemed. Had they confined themselves to the simple recital of facts, they would nearly all have agreed. But they have written history—they have written philosophical history, and have each attained a diametrically opposite result. With them facts disappear under their philosophical amplifications; the truth escaped with the facts, and yet all conscientiously believe that they have written the truth.
They have all been subjected, more or less, to the influence of the times, of their epoch, of their education: positive impartiality is not given to man. To obtain from an individual the truth, the true truth, you must take from him all the passions, both good and evil, of human nature: it is necessary, in a word, that he should not be a man.
Take Cromwell as an example: read all that has been successively written on the character of this extraordinary man, under the consulate, the empire, and the restoration: you will have three opinions, based upon facts identically the same, but presented in a different manner: you will have three opinions equally conscientious, perhaps, yet absolutely different from each other.
No man can ever have sufficient power over himself to cast off completely all the spirit, all the influence of party, of caste, of sect, of theory, of a school, or of a coterie. With a philosophical historian, whether he call himself Bossuet or Chateaubriand, facts do not control the reasoning; but the original opinions, the intimate convictions of the writer, control the facts, and distort them according to his necessities, because, above all things, he desires to be logical, and always believes himself supported by reason.
The reader will remark that I have only spoken of honest historians; and I have proved that it is vain to seek for truth among their writings. But if I had referred to those authors of another class, who write to defend or support a particular cause, or a political or religious party, I should in that case have found the truth sacrificed, not to a sentiment in a certain degree honourable but to a sordid and base interest. With them truth does not bend under the weight of logic, but is thrown aside to make room for lies.