Science as we know it today—making discoveries through the systematic observation of and controlled experimentation with physical realities—is the descendant of the philosophy of nature developed by classical and Medieval thinkers. The course will open with the vision of ultimate reality and meaning developed by Thomas Aquinas in the high Middle Ages and then skip to current challenges to the Catholic view of the natural world that have been posed by modern philosophies of science. We are engaged in a war of worldviews that can only be resolved through sound philosophical reasoning.