The Fundamental Principle of Morality According to Kant

According to Kant, the fundamental principle of morality must be a categorical, rather than a hypothetical imperative, because an imperative based on reason alone is one that is a necessary truth, is a priori, and is one that applies to us because we are rational beings capable of fulfilling our moral obligations. Kant explains this essential truth is how "an action as objectively necessary in itself apart from its relation to a further end". This refers to how if the supreme principle of morality was only a possible truth, then its force as a principle would be dependent on what may happen in other propositions. So being, the SPM would not be guiding the choice and action of a morally good will. This means that because morality holds sovereignly of what we desire or of any other facts about us, the truths themselves are not/cannot be contingent. Moral imperatives must be categorical imperatives then, because they would apply with unconditional necessity to all rational beings. He argued that this conformity can nevertheless be shown to be essential to rational agency, because of his belief that a rational will must be regarded as autonomous, or self-governing in the sense of being the author of the law that binds it. The fundamental principle of morality, or the CI — is then none other than a law of an autonomous will. Likewise, it is the decisive grounds for viewing each person as possessed/deserving of equal worth and equal respect. Also, it is known to be a priori because it is by reason alone, independent of experience that we know such truths. This means that the moral law originates in pure reason and is enunciated by an a priori synthetical judgment --a priori because it has its reason, not in experience, but in the mind itself; synthetical, because it is formed not by the analysis of a conception, but by an extension of it.
In contrast, the hypothetical imperative is an imperative based on inclination or desire that represents "the practical necessity of