In an interesting juxtaposition, two very different men were born on the same date: Abraham Lincoln and Charles Darwin. Both men would exert influence on their societies, and ultimately the world; both exemplified questions which are relevant to the very core of human existence. Yet they represent opposites.
Lincoln would stress the value of every human life, and therefore the law's obligation to treat all humans equally; he saw principles of justice as arising from the rational design of the universe.
Darwin, assuming that irrational chance governed the universe, stressed that life spontaneously arose from a random mix of inanimate chemicals; determined by the physical patterns of molecular reactions, humans make no significant choices, and have no deeper meaning in life.
Lincoln faced the terrifying weight of existential choices which a human can authentically make, including the responsibility for the outcomes; but he opened the door for a sense of hope that freedom and meaning are possible.
Darwin envisioned a world in which humans were free from the terrifying thought of having to take responsibility for their choices and actions; but in the process, he lost the possibility of an authentic existential freedom, of any principled rationality in the structure of the universe, and of transcendental meaning in human life.