We learn from failure, not from success!

I am all in a sea of wonders. I doubt; I fear; I think strange things, which I dare not confess to my own soul.

Our toil must be in silence, and our efforts all in secret; for this enlightened age, when men believe not even what they see, the doubting of wise men would be his greatest strength.

A single lie discovered is enough to create doubt in every truth expressed.

I was in doubt, and then everything took a hue of unreality, and I did not know what to trust, even the evidence of my own senses. Not knowing what to trust, I did not know what to do; and so had only to keep on working in what had hitherto been the groove of my life. The groove ceased to avail me, and I mistrusted myself.