Does life require a purpose? I suppose how we define purpose and life is important if we are to attempt an answer that is satisfactorily supported with evidence. Here’s my sketchy take on the subject.
All coherent objects in nature must have some capacity to nourish and or defend their coherence in the context of the environmental womb in which it is situated, otherwise it would not exist over time. In our case, we are nested layers of sophisticated behavioral architectures that support this continuing coherence. The behaviors involve things of adaptive value such as breathing, drinking, eating, obtaining shelter, as well forming social bonds, mating and the like because of the adaptive (purposeful) advantage of these behaviors. This macro behavior, along with a host of micro internal relationships carry out a singular purposeful theme of nourishing and or defending coherence. This is expressed on many levels with many variations built around this unified theme of nourishing and-or defending coherence in the context of the environment. This is what defines a coherent entity, whether an idea, what is communicated by the totality of behaviors we express through our life.
The inherent purpose communicated through our nature is why we are not satisfied unless we do something significant – something of nourishing and-or protective value with respect to the common body of relationships we live in, are part of, and depend on for life. Finding that thing we can do to contribute to the nourishing and or protective value to the community of relationships that defines our common experience of life is a story written right into the fabric of life. We never meet persons who are both malignantly selfish and satisfied at the same time. This inherent purpose written into the complex dynamic coherent structures such as ourselves sets the tone for whether we will be satisfied or frustrated, whether we will do what is significant, or move on the currents in meaningless directions.
Here is a look at some “nourish and defend” activity on a molecular scale.
The Wisdom Of Life 