In my case Pilgrim's Progress consisted in my having to climb down a thousand ladders until I could reach out my hand to the little clod of earth that I am.
There is no such thing as a pure introvert or extrovert. Such a person would be in the lunatic asylum.
The word 'belief' is a difficult thing for me. I don't believe. I must have a reason for a certain hypothesis. Either I know a thing, and then I know it - I don't need to believe it.
Mistakes are, after all, the foundations of truth, and if a man does not know what a thing is, it is at least an increase in knowledge if he knows what it is not.