Men are limited by the knowledge of their minds, the worth of their characters and the principles upon which they are building their lives.

The quote argues that human potential is constrained from the inside out. “Knowledge of their minds” points to the limits imposed by ignorance, unexamined assumptions, or narrow intellectual horizons; “worth of their characters” suggests that ability without integrity caps a person’s influence and trustworthiness; and “principles…building their lives” frames life as a construction project whose stability depends on foundational commitments. In Cole’s moral and religious register, the statement functions as a call to self-governance: expand understanding, cultivate virtue, and choose durable principles, because these internal factors ultimately determine the scale and quality of one’s life more than external opportunity.