By and large ethics is the study of how and why one should act good. But that’s just part of the equation. Ethics seek to quantify and explain human behavior, and despite the presence of true human goodness, one can’t deny that people have a dark streak. Some philosophers have explored that darkness and negativity as it relates to ethics. For instance, if being good is part of life, then isn’t being “bad” also a part of life? And if it’s natural to be selfish or cruel, then could it also be considered ethical to be selfish or cruel? Some philosophers went down this road, as did others who explored the ethical ramifications of the possibility that humanity exists apart from any sort of moral or divine framework whatsoever.
• Niccolò Machiavelli. In the sixteenth century he urged people to use ethics to manipulate others and strive at all costs to obtain and keep power, often ruthlessly. Why? Because it is in our nature to do so.
• Jean-Paul Sartre. He was a twentieth-century proponent of existentialism, or the idea that life has no innate meaning and man has no true purpose. This lack of predetermination means that all humans have freedom and choice, and utter and complete free will to live a life as they see fit on their own terms.
• Friedrich Nietzsche. This nineteenth-century German philosopher wrote about man’s duty to create life in one’s own image—to make oneself as great and varied a person as possible, and to reject traditions and institutions along the way, for they were outdated and held back true moral growth.
• Arthur Schopenhauer. Diverging from most all other moral philosophers, this early nineteenth-century philosopher thought that the universe is an essentially irrational place, which has major consequences on how humans behave ethically.
• Ludwig Wittgenstein. An important twentieth-century philosopher, he called all of moral philosophy into question by questioning the veracity of the one real tool philosophers have at the ready: their words.