It is true that the same Cartesian spirit which did so much for physics was already laying the foundations of critical method in history before the seventeenth century was out;[61] but the modern conception of history as a study at once critical and constructive, whose field is the human past in its entirety, and whose method is the reconstruction of that past from documents written and unwritten, critically analysed and interpreted, was not established until the nineteenth, and is even yet not fully worked out in all its implications.
