The Sleepwalkers (227 page)

The
Assayer
was
written
in
the
form
of
a
letter
to
a
friend,
Monsignor
Cesarini,
Chamberlain
to
the
Pope.
It
starts
with
a
tirade
against
all
who
tried
to
rob
Galileo
"of
the
glory
of
his
discoveries",
to
whose
ranks
he
now
added
Marius
von
Gunzenhausen,
the
discoverer
of
the
spiral
nebula
in
Andromeda
(the
first
nebula
observed).
It
is
in
this
context
that
the
passage
occurs
which
I
have
quoted
already:

"You
cannot
help
it,
Signor
Sarsi,
that
it
was
granted
to
me
alone
to
discover
all
the
new
phenomena
in
the
sky
and
nothing
to
anybody
else.
This
is
the
truth
which
neither
malice
nor
envy
can
suppress."

The
Assayer
then
sets
out
to
demolish
the
reputation
of
Tycho
by
talking
of
his
"alleged
observations",
and
by
calling
comets
"Tycho's
monkey-planets".
He
also
explains
the
reason
which
forced
him
to
break
his
previous
resolve
to
publish
no
more:
Galileo's
enemies,
having
unsuccessfully
tried
to
steal
his
discoveries,
now
try
to
attribute
to
him
"the
works
of
others"
–
namely,
Guiducci's
tract.
He
indignantly
denies
having
had
any
part
in
that
tract
beyond
discussing
the
subject
with
Guiducci;
but
now
he
has
to
break
his
silence
"to
discourage
those
who
refuse
to
let
sleeping
dogs
lie,
and
who
stir
up
trouble
with
men
that
are
at
peace".

The
major
part
of
the
work
consists
of
sarcastic
refutations
of
everything
Grassi
had
said,
regardless
whether
the
poor
man
had
blundered
–
which
he
often
had
–
or
hit
on
the
truth.
Thus
Grassi
had
maintained
that
projectiles
get
heated
by
friction
with
the
air;
Galileo
answered
that
they
got
not
hotter
but
colder:
"trying
to
pulverise
the
air
is
as
great
a
waste
of
time
as
grinding
water
in
the
proverbial
mortar".
⁵
As
it
so
often
happens,
Grassi
had
tried
to
prove
a
good
case
by
a
bad
argument:
he
quoted
Suidas
(a
tenth
century
Greek
lexicographer)
to
the
effect
that
the
Babylonians
cooked
eggs
by
whirling
them
swiftly
through
the
air
on
a
sling.
This
gave
Galileo
an
opportunity
of
making
mincemeat
of
his
opponent
in
a
hilarious
passage
which
is
often
quoted,
(but
mostly
without
mention
of
the
context):

"If
Sarsi
wants
me
to
believe
with
Suidas
that
the
Babylonians
cooked
their
eggs
by
whirling
them
in
slings,
I
shall
do
so;
but
I
must
say
that
the
cause
of
this
effect
was
very
different
from
what
he
suggests.
To
discover
the
true
cause
I
reason
as
follows:
'If
we
do
not
achieve
an
effect
which
others
formerly
achieved,
then
it
must
be
that
in
our
operations
we
lack
something
that
produced
their
success.
And
if
there
is
just
one
single
thing
we
lack,
then
that
alone
can
be
the
true
cause.
Now
we
do
not
lack
eggs,
nor
slings,
nor
sturdy
fellows
to
whirl
them;
yet
our
eggs
do
not
cook,
but
merely
cool
down
faster
if
they
happen
to
be
hot.
And
since
nothing
is
lacking
to
us
except
being
Babylonians,
then
being
Babylonians
is
the
cause
of
the
hardening
of
eggs,
and
not
friction
of
the
air.'"
⁶

But
in
between
these
brilliant
irrelevancies
and
sophistries,
there
are
again
passages
scattered
about
which
have
become
classics
of
didactic
literature.
They
concern
the
principles
of
scientific
reasoning,
experimental
procedure,
the
philosopher's
duty
to
be
sceptical
about
authorities
and
principles
that
are
being
taken
for
granted.
Above
all,
Galileo
outlines
a
principle
which
became
of
outstanding
importance
in
the
history
of
thought:
the
distinction
between
primary
qualities
in
nature
such
as
the
position,
number,
shape
and
motion
of
bodies,
and
secondary
qualities
such
as
colours,
odours,
and
tastes,
which
are
said
to
exist
only
in
the
observer's
consciousness.
⁷

"To
excite
in
us
tastes,
odours,
and
sounds
I
believe
that
nothing
is
required
in
external
bodies
except
shapes,
numbers,
and
slow
or
rapid
movements.
I
think
that
if
ears,
tongues,
and
noses
were
removed,
shapes
and
numbers
and
motions
would
remain,
but
not
odours
or
tastes
or
sounds.
The
latter,
I
believe,
are
nothing
more
than
names
when
separated
from
living
beings..."