Full Idea
A human being is a starting point of some actions, and he alone of animals; for of nothing else should we say that it acted.
Gist of Idea
Only a human being can be a starting point for an action
Source
Aristotle (Eudemian Ethics [c.333 BCE], 1222b19)
Book Reference
Aristotle: 'Eudemian Ethics I,II and VIII', ed/tr. Woods,Michael [OUP 1992], p.21
A Reaction
It is a standard dogma that the idea of free will does not occur in Plato or Aristotle, but this looks awfully like it. I don't agree about animals. You watch them judging whether they can make a leap, and then doing it.
Related Idea
Idea 22508 Unlike in inanimate things, in animate things actions have more than one starting point [Aristotle]