- Welcome to the U. S. and Canada Obsidian and FGV (Fine-Grained Volcanic Toolstone) Source Mapping Project home page. For many years, we’ve been chasing down obsidian and FGV sources in the western United States and have promised that someday - when enough source information was finally available - we would begin creating maps that illustrate the geographic patterning of these archaeologically-significant prehistoric sources of natural glass and volcanic toolstone. That day has finally come and we are currently in the process of assembling and producing source maps for the western United States and Canada. Along with a few states (and provinces) for which we still lack good GIS coverages or adequate source data, we’re currently working on regional maps that illustrate the spatial ranges of several geographically-extensive sources.
- Cogito, ergo sum (Wikipedia)
The Latin cogito, ergo sum, usually translated into English as “I think, therefore I am”, is the “first principle” of René Descartes’s philosophy. He originally published it in French as je pense, donc je suis in his 1637 Discourse on the Method, so as to reach a wider audience than Latin would have allowed. It later appeared in Latin in his Principles of Philosophy, and a similar phrase also featured prominently in his Meditations on First Philosophy. The dictum is also sometimes referred to as the cogito. As Descartes explained in a margin note, “we cannot doubt of our existence while we doubt.” In the posthumously published The Search for Truth by Natural Light, he expressed this insight as dubito, ergo sum, vel, quod idem est, cogito, ergo sum (“I doubt, therefore I am — or what is the same — I think, therefore I am”). Antoine Léonard Thomas, in a 1765 essay in honor of Descartes presented it as dubito, ergo cogito, ergo sum (“I doubt, therefore I think, therefore I am”).