Final answer:
Kant asserts that our sovereign master should be our rational will, enabling us to act according to the categorical imperative, which ensures moral actions can be universalized. He champions good will and rationality as central to human dignity and the foundation for universal moral laws.
Step-by-step explanation:
According to Immanuel Kant, our sovereign master should be our own rational will, which guides us to act morally. Kant emphasizes the significance of good will and our capacity for rational thought as the defining characteristics of humanity, placing moral action and rationality at the core of human dignity and freedom. We determine the morality of our actions based on their ability to be universalized, as stated in Kant's categorical imperative: "Act only according to that maxim whereby you can, at the same time, will that it should become a universal law". This principle is meant to ensure that our actions can be applied as a universal rule, reflecting the innate moral law that can be discovered a priori by reason alone, beyond the influence of impulses, emotions, and varying cultural or religious beliefs. This firm stance on rationality and duty stands separate from the assessment of outcomes, prioritizing unconditional moral principles over conditional values.