DOC.
350
JUNE
1917 339
extended
over a
closed
curve
in
the
“Riemann foliated”
qv-space
is
now
considered.
This
integral
vanishes when the
curve can
be contracted
continuously
into
a
point
which,
owing
to
the
“Riemannization,”
is
by
no
means
the
case
for all
curves.
Now,
the
quantum
rule
requires quite simply
that
for
any
closed
curve,
ƒ
EPvdqv
=
nh
has to
apply. Epstein’s special
case
is
simply
that
each
pv
depends only
on
the
related
qv.[3]
Handsome
though
this
is,
it
is just
limited to
the
special
case
where
the
pv’s can
be described
as
(multiple)
functions
of
the
qv's.
It
is interesting
that
precisely
this limitation
removes
the
validity
of
statistical
mechanics. For
it
presupposes
that,
at
the
recurrence
of
the
qv's,
the
pv's
of
a
system
left to itself
gradually
adopt
all value
systems
compatible
with the
energy
principle.
It
seems
to
me
that
real mechanics
is
such
that the
existence
of
the
integrals
(which
preclude
the
validity
of
statistical
mechanics)
is
already
secured
by
virtue
of
its
general
foundations.
But
how to
implement
this??
I shall be
glad
to write to Onnes.[4]
Have
you seen
Nernst?
He
was
in
Hol-
land
to find out whether his
pilot
son,
who has
crashed, is
dead. The
other
died
in action
right
at
the
beginning
of
the
war.
Old Jehovah
is
still
around.[5]
Un-
fortunately He
also smites
the
innocent,
and He smites the
guilty terribly
with
blindness
so
that
they cannot feel
guilt.
So
where does
He
get
the
right
to
punish
and
crush?
Also from
force,
perchance?[6]
I
have become much
more
tolerant,
without
changing
my
views in
principle
in the least.
I
see
that
often
the
most
power-hungry
and
politically
extreme
people
could
not
kill
a
fly
as
private
in-
dividuals.
A
delusion of
epidemic proportions
is afield
which,
after
producing
immeasurable
suffering,
will
vanish
again,
so
the
generation
after
the
next
can
gasp
at
it
as
something completely
monstrous
and
incomprehensible.
I
am
very
eager
to
see
Burgers’s
new paper.[7]
You
yourself complain
again
about
yourself
and
are
not satisfied with
yourself.
Just think
how
insignificant
it
will
be
20
years
from
now
how
one
knocked
about
on
this
Earth,
provided
no wrong was
done.
It
is
all
the
same
whether
you
or someone
else
has written this
or
that
paper.
You
are
certainly
never
mindless,
except
for when
you
happen
to
be
contemplat-
ing
whether
you
are
mindless
or
not.
So, away
with
the
hypochondriac! Enjoy
yourself
with
your family
in
the
fair land of
the
living!
Affectionate
greetings, yours,
Einstein.