This quote is exploring the concept of purpose and the driving force behind our actions. The first part, "What for? What am I to unify my being for?" is asking about the reason or motivation behind our efforts to become a unified, coherent self. Are we doing it for personal gain or for a higher purpose?

The second part, "The reply is: Not for my own sake," suggests that the motivation should not be selfish. Instead, the aim of unifying one’s being should be for something greater than oneself. This could be for the benefit of others, for the betterment of society, or in pursuit of a higher moral or spiritual value.

In today’s world, this idea is highly applicable. In an era characterized by individualism and self-centeredness, this quote serves as a reminder that our actions and personal development should not be driven solely by personal gain. Instead, we should strive for growth and improvement for the sake of contributing to something bigger than ourselves – be it our community, our society, or the world at large.

In terms of personal development, this quote encourages us to question our motivations and to align our actions with values that extend beyond our personal desires. It pushes us to consider the impact of our actions on others and to strive for a sense of unity and coherence in our lives that is rooted in selflessness, rather than self-interest.