The Fifth Way uses Aristotle's final cause. Aristotle argued that a complete explanation of an object will involve knowledge of how it came to be (efficient cause), what material it consists of (material cause), how that material is structured (formal cause), and the specific behaviors associated with the type of thing it is (final cause). The concept of final causes involves the concept of dispositions or "ends": a specific goal or aim towards which something strives. For example, acorns regularly develop into oak trees but never into sea lions. The oak tree is the "end" towards which the acorn "points," its disposition, even if it fails to achieve maturity. The aims and goals of intelligent beings is easily explained by the fact that they consciously set those goals for themselves. The implication is that if something has a goal or end towards which it strives, it is either because it is intelligent or because something intelligent is guiding it.