Abstract
All these activities of living beings, and the functioning of their organs, and the functioning of instruments demand a teleological explanation. Why do human beings toil? Why do living beings try to maintain the activities of the organism? What are the functions of specific organs or instruments? Intelligible answers can be given in teleological terms. Of course, one could ask many questions about these situations that would not require the teleological explanation; for example, questions concerning the mechanical structure of living beings or of instruments. Yet this fact would not eliminate the legitimacy nor the utility of the teleological category.