Never underestimate your own ignorance.
Imagination is everything. It is the preview of life's coming attractions.
I am enough of an artist to draw freely upon my imagination.
If I am right the Germans will say I was a German, and the French will say I was a Jew; If I am wrong the Germans will say I was a Jew and the French will say I was a German.
Anyone can repeat a technical explanation they read in a text-book or blog post.
In my relativity theory I set up a clock at every point in space, but in reality I find it difficult to provide even one clock in my room.