Immanuel Kant was born in 1724 in the East Prussian town of Königsberg and lived there practically all his life. He came from a deeply pious Lutheran family, and his own religious convictions formed a significant background to his philosophy. Like Berkeley, he felt it was essential to preserve the foundations of Christian belief.
Kant became Professor of Logic and Metaphysics at the University of Königsberg in 1770 and taught there for most of his life. He was also greatly interested in science and published works on astronomy and geophysics.
His three most significant works were published later in life. The Critique of Pure Reason came out in 1781, followed in 1788 by the Critique of Practical Reason and in 1790 by the Critique of Judgment. The Critique of Pure Reason is one of the most important works in the whole of philosophy. Unfortunately it is also one of the most unreadable - Kant himself described it as dry and obscure.
Kant had generally been an outgoing and friendly man but towards the end of his life his mental faculties and his sight deteriorated badly. He died a shadow of his former self, aged 80. One of his most quoted sayings is carved on his gravestone in Königsberg: "Two things fill my mind with ever-increasing wonder and awe, the more often and the more intensely the reflection dwells on them: the starry heavens above me and the moral law within me".
Kant believed that there are clear limits to what we can know. You could perhaps say that the mind's "glasses" set these limits.
The philosophers before Kant had discussed the really "big" questions - for instance, whether man has an immortal soul, whether there is a God, whether nature consists of tiny indivisible particles, and whether the universe is finite or infinite. Kant believed there was no certain knowledge to be obtained on these questions. In such great philosophical questions, he thought that reason operates beyond the limits of what we humans can comprehend. At the same time there is in our nature a basic desire to pose these questions. When, for example, we ask whether the universe has always existed, we are asking about a totality of which we ourselves are a tiny part. We can therefore never completely know this totality.
According to Kant there are two elements that contribute to our knowledge of the world - sensory perception and reason. The material of our knowledge comes to us through the senses, but this material must conform to the attributes of reason.
When we wonder where the world came from, however - and then discuss possible answers - reason is in a sense on hold. It has no sensory material to process, no experience to make use of, because we have never experienced the whole of the great reality of which we are a tiny part.
In such weighty questions as to the nature of reality, Kant showed that there will always be two contrasting viewpoints that are equally likely or unlikely, depending on what our reason...