Immanuel Kant: Philosophy and Key Works

Posted on Jan 21, 2025 in Philosophy and ethics

Immanuel Kant

1. Life and Works

1.1. Life (Königsberg, 1724 – 1804)

Influenced by the school of Christian rationalism and the skepticism of empiricist David Hume, Kant undertook the task of critically analyzing Reason.

He divided the area of Reason’s capabilities into the areas defined by the following questions:

  1. What can I know?
  2. What should I do?
  3. What may I hope?
  4. What is man?

1.2. Works

  • 1.2.1. First Period: Precritical
  • 1.2.2. Second Period: Critical
  • Critique of Pure Reason (theoretical) (1781)
  • Groundwork of the Metaphysics of Morals (1785)
  • Critique of Practical Reason (1788)
  • Critique of Judgment (1790)
  • Religion within the Limits of Reason Alone (1793)

2. The Critique of Pure Reason: What Can I Know?

This work justifies the scientific nature of mathematics and physics, which are based on pure a priori forms of sensibility (space in geometry and time in number) and the Understanding (categories: quantity, quality, relation, modality) to develop synthetic judgments a priori (bringing knowledge, universality, and necessity).

Phenomena (the given, sensitivity to the conditions of space-time) and noumena (the thing-in-itself, the purely intelligible).

Transcendental Apperception: refers to the “I think” that accompanies all my representations.

Metaphysics as a science is impossible. God (an illegitimate synthesis from disjunctive judgments), the Soul (an illegitimate synthesis from categorical judgments), and the World (an illegitimate synthesis from hypothetical judgments) are only regulative ideas of reason.

The existence of God cannot be proven by any of the traditional arguments: 1) the ontological proof, 2) the cosmological proof, and 3) the physico-theological proof.

Fallacies of reason (or unprovable contradictory judgments on the Soul). The categories of Understanding cannot be applied to the “I think”: what thinks can never be predicated. The “subject” cannot become the “object” of the “subject” itself, which is irreducible to an “object”.

Antinomies of Reason: contradictory statements on the World.

3. The Critique of Practical Reason: What Should I Do?

3.1. Kant’s Ethics

3.1.1. Being (What I Know) and Shall Be (What Should I Do?)
3.1.2. Moral Imperatives and Standards
3.1.2.1. Types of Imperatives
  • Hypothetical Imperative: orders something as a means to an end.
  • Categorical Imperative: orders something as an absolute end, an imperative for its own sake.
3.1.2.2. Moral Standards
  • Hypothetical imperatives cannot be moral standards because: 1) their validity is conditional, and 2) we must appeal to experience to determine our behavior and knowledge. Hypothetical imperatives are judgments of experience, not moral standards.
  • Categorical imperatives are not generally valid: they are often met in order to avoid the negative consequences arising from their breach.
3.1.2.3. Kant’s Categorical Imperative
  • Types of Actions
    • Actions in accordance with duty, according to the consequences.
    • Actions out of respect for duty, for duty’s sake alone.
  • Distinction between Matter and Form of Moral Law
  • Formulations of 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.”
    • “Act in such a way that you treat humanity, whether in your own person or in the person of any other, never merely as a means to an end, but always at the same time as an end.”
  • Dignity and the Kingdom of Ends
3.1.2.4. Material Ethics and Formal Ethics
  • Material Ethics: These are empirical (a posteriori), their precepts are hypothetical, relative, and heteronomous.
  • Formal Ethics: These are a priori, their precepts are categorical, universal, and autonomous.

3.2. Conditions of Possibility of Morality and Assumptions of Morality

  • Freedom: For there to be a “moral subject,” we must believe that the will is free to decide in a phenomenal world subject to the law of cause and effect.
  • Immortality of the Soul
  • Existence of God, which makes possible the highest good (the attainment of happiness for those who comply with morality; happiness would be achieved in the hereafter, the “kingdom of the saints”).