July 12. Paris. I must have lost my head during the last few
days! I must be the plaything of my enervated imagination, unless
I am really a somnambulist, or I have been brought under the
power of one of those influences--hypnotic suggestion, for
example--which are known to exist, but have hitherto been
inexplicable. In any case, my mental state bordered on madness,
and twenty-four hours of Paris sufficed to restore me to my
equilibrium.

Yesterday after doing some business and paying some visits, which
instilled fresh and invigorating mental air into me, I wound up
my evening at the Theatre Francais. A drama by Alexander Dumas
the Younger was being acted, and his brilliant and powerful play
completed my cure. Certainly solitude is dangerous for active
minds. We need men who can think and can talk, around us. When we
are alone for a long time, we people space with phantoms.

I returned along the boulevards to my hotel in excellent spirits.
Amid the jostling of the crowd I thought, not without irony, of
my terrors and surmises of the previous week, because I believed,
yes, I believed, that an invisible being lived beneath my roof.
How weak our mind is; how quickly it is terrified and unbalanced
as soon as we are confronted with a small, incomprehensible fact.
Instead of dismissing the problem with: "We do not understand
because we cannot find the cause," we immediately imagine
terrible mysteries and supernatural powers.

July 14. Fete of the Republic. I walked through the streets, and
the crackers and flags amused me like a child. Still, it is very