If you fail to participate intelligently on a fairly regular basis, your grade will be damaged. If you talk without preparation, you will not do yourself any good. As noted above, there are two mid-terms, all essay exams and a comprehensive final exam. You must have a documented excuse from the Dean's office to make up an exam. If you do not and miss an exam, you will receive a zero on the test.
Zeros are awfully hard to recover from.
It does not mean that you attended class and have a vague idea of what's going on here. If you are not going to work hard in my class, I recommend you drop it now. The choice is yours. You will prepare two papers during the semester. These are to be around 1500 words long, are to be typed and footnoted as per proper style.