y, still less
could I follow when they began to discuss Kant's _Kritik der reinen
Vernunft_. One of my friends, whom I looked up to as a great
authority, confessed that he had read the book again and again, but
could not understand the whole of it. My curiosity was much excited,
and once, while he was taking a walk with me, I asked him very timidly
what Kant's book was about, and how a man could write a book that
other men could not understand. He tried to explain what Kant's book
was about, but it was all perfect darkness before my eyes; I was
trying to lay hold of a word here and there, but it all floated before
my mind like mist, without a single ray of light, without any way out
of all that maze of words. But when at last he said he would lend me
the book, I fell on it and pored over it hour after hour. The result
was the same. My little brain could not take in the simplest ideas of
the first chapters--that space and time were nothing by themselves;
that we ourselves gave the form of space and time to what was given us
by the senses. But though defeated I would not give in; I tried again
and again, but of course it was all in vain. The words were here and I
could construe them, but there was nothing in my mind which the words
could have laid hold on. It was like rain on hard soil, it all ran
off, or remained standing in puddles and muddles on my poor brain.

At last I gave it up in despair, but I had fully made up my mind that
as soon as I went to the University I would find out what philosophy
really was, and what Kant meant by saying that space and time were
forms of our sensuous intuition. I see that, accordingly, in the
summer of 1841, I attended lectures on Aesthetics by Professor Weisse,
on Anthropology by Lotze, and on Psychology by Professor Heinroth, and
I slowly learnt to distinguish between what was going on within me,
and what I had been led to imagine existed outside me, or at least
quite independent of me. But before I had got a firm grasp of Kant,
of his forms of intuition, and the categories of the understanding, I
was thrown into Hegelianism. This, too, was at first entire darkness,
but I was not disheartened. I attended Professor Weisse's lectures on
Hegel in the winter of 1841-2, and again in the winter of 1842-3 I
attended his lectures on Logic and Metaphysics, and on the Philosophy
of History. He took an interest in me, and I felt most strongly
attracted by him. Soon after I joined his Philosoph