In dealing with action principles, many textbooks on variational calculus or mechanics add a digression on history or even on philosophy. This is a remnant of a long tradition of discussion among physicists and philosophers, mainly on the so-called "Principle of Least Action". One must admit that this subject is not among the hottest topics in the contemporary debate on the foundations of physics. It is moreover a common opinion that the philosophical notions mentioned in connection with the principle, teleology and final causes, should be kept out of physics. A very decided statement of this spirit can be found in Ref. [1] (p. 155) as the conclusion of an entire book on variational principles: "Hence the teleological approach in exact science can no longer be a controversial issue; it is not only contrary to the whole orientation of theoretical physics, but presupposes that the variational principles themselves have mathematical characteristics which they de facto do not possess." For the authors variational principles are a mere reformulation of the equations of motion, which is physically equivalent to them.