Immanuel Kant Biography

Immanuel Kant

Immaneuel Kant is regarded as one of the most influential thinkers of the late 18th century’s Enlightened period. He was a German philosopher and professor famous for his three treatises: Critique of Pure Reason, Critique of Practical Reason, and Critique of Judgement.

Early Life of Kant

Immanuel Kant (1724-1804), was born on April 22, 1724, in the Prussian city of Königsberg (now Kalinigrad, Russia). He was not that adventurous and had little interest in music or the arts. His passion was in logic, mathematics and science.

Kant’s Three Critiques

Kant’s influence primarily comes from the first two of his three Critiques, the Critique of Pure Reason, and the second one, a shorter and more lucid Critique of Practical Reason. The third one, Critique of Judgement, concerned with ideas of beauty and purpose, received less attention.

Critique of Pure Reason

Kant’s first critique, Critique of Pure Reason, is considered his greatest work. He was concerned to justify metaphysics as a legitimate subject of inquiry. He set out to determine the limits and correct use of reason, in particular, to bring out into disrepute between the rationalists and the empiricists.

The rationalists claimed that metaphysical judgements – the fundamental principles upon which all knowledge is based – are known and justified purely by the intellect. On the other hand, the empiricists claimed that the human mind is like a blank sheet waiting to be written based upon experience.

Kant tried to find a way to synthesize these two opposing views. His basic insight sprang from the question, “what are the necessary preconditions for having any experience at all?” He argued that in order for human beings to be able to interpret, the human mind had to impose certain structures on its incoming sense-data.

The Categories: Twelve Fundamental Judgements

Kant attempted to define these in terms of twelve fundamental judgements he called the Categories (substance, cause and effect, reciprocity, necessity, possibility, existence, totality, unity, plurality, limitation, reality and negation) which could only be applied within a spatial and temporal framework. Kant claimed that both the Categories and space and time, which he called ‘forms of intuition,’ were imposed on phenomenal experience by the human mind in order to make sense of it.

Immanuel Kant called his idea of the Categories the ‘Copernican revolution.’ Like Copernicus, who turned the traditional idea of the sun orbiting the earth on its head, Kant solved the problem of how the mind acquires knowledge from experience by arguing that the mind imposes principles upon experience to generate knowledge.

Critique of Practical Reason

Just as Kant had laid down laws of thought in his first Critique, in his second, Critique of Practical Reason, he set out to deal with problems of ethics. He discussed the relationship between morality and reason, duty, and God. He claimed to have discovered a universal moral law which he called ‘the categorical imperative.’

Critique of Judgement

This third book Critique of Judgement contains a discussion of aesthetics, along with the nature of judgements that pertains to what is beautiful.

Kant’s Legacy

In addition to his three treatises, Kant produced several essays in support of religious liberalism and enlightenment. He died on February 12, 1804, aged 80. Immanuel Kant claimed to have discovered universal principles of thought applicable to mankind for all time.

Recommended Works by Kant

  • Critique of Pure Reason, 1781
  • Critique of Practical Reason, 1788
  • Critique of Judgement, 1790


  1. Biographical Dictionary, edited by Una Mcgovern, Chambers (2002)
  2. Illustrated Biographical Dictionary, edited by John Clark, Chancellor Press (1994)
  3. Philosophy, the Great Thinkers, by Philip Stokes, Capella (2007)