Immanuel Kants principles on morality.

Write a 4 page paper about the groundwork for the metaphysics of morals on Immanuel Kant using Steven M.Cahn Classics of Political & Moral Philosophy Oxford university press(2012) , second edition. Emphasis should focus on three particular texts in the textbook ;
The  first one is when Kant says,” We can call any philosophy that is based on experience empirical. We can call it pure philosophy  if it sets forth its teachings entirely on the basis of a priori principles. When pure philosophy is merely formal, it is called logic; but  if it limited to specific objects of the understanding, pure philosophy is then called metaphysics.” Second text on morals, ” A metaphysics of morals is thus indispensably necessary not merely because one wants to investigate and understand the source of practical principles which are present a priori in our reason, but because morality itself remains subjected to all sorts of corruption as long as this guiding thread, this ultimate norm for correct moral judgement, is lacking. For if any action is to be morally good, it is not enough that it should conform to the moral law- it must also be done for the sake of the law.” Lastly, but not least i have to make a strong argument against Kant’s text, ” Beings whose existence depends not on our will but on nature still have only a relative value as means and are therefore called things, if they lack reason. Rational beings, on the other hand ,are called persons, because,their nature already marks them out as ends in themselves that is as something which ought not to be used merely as a means and imposes restrictions on all choice making .” This assignment requires critical, thinking and writing, but no personal opinions. Using the three texts from Kant  above  to relate his deontology to the essay written by Tom Regan, “The Case for Animal Rights.”