From
William
P SHEEHAN
© . . . . . . . . . . Dear Masatsugu,
I am sorry to hear about the health problems -- these are
always alarming, and I hope that all the test prove that the hematuria is of no consequence. My friend John Westfall, who has completed
the text of a book on the transit of Venus, recently suffered a detached retina
and this had to be operated on twice. It
is exceedingly poor timing to have these things happen with Mars approaching,
but they cannot be helped! I hope you will rest as you can and not overwork yourself
with Mars.
Of course, I am looking forward exceedingly to the visit
to
With my very warmest regards,
(
© . . .
. . . . . . .Dear Masatsugu,
Thought you might like a copy of the sidebar I wrote for *Mercury*, the
Astronomical Society of the Pacific's magazine, on Martian canals.
I do think the Pacific designation should be comprehensive
and include observers on both sides of the basin.
David Strauss gave me a grand list of publications on
With best regards, and eager for news (I hope
all favorable) regarding your health.
(
Sidebar: Eyewitness
Testimony: the Canals of Mars
One of the questions
that comes up in courtroom testimony is the reliability
of eyewitness testimony. According to psychologist Elizabeth F. Loftus, writing
in Eyewitness Testimony (
"Whether we are concerned with the identification
of a person or the accurate recounting of the details of an event... eyewitness
testimony is very believable and can wield considerable influence over the
decisions reached by a jury; on the other hand, eyewitness testimony is not
always reliable. It can be flawed simply
because of the normal and natural memory processes that occur whenever human beings
acquire, retain, and attempt to retain information."
The debate over the
reality of the Martian network on Mars depended on a form of "eyewitness
testimony." It was the observer's
testimony at the eyepiece of the telescope, under conditions in which the image
of a
planet -- tens of millions of kilometers from the Earth
and swimming in a sea of air -- moved and changed and trembled.
Psychologists have
learned that a number of factors can influence the reliability of eyewitness
testimony. One of the factors is
exposure time -- subjects are much more accurate at remembering a face they
studied for a longer period of time than a face they examined only
fleetingly. Another factor affecting
reliability of testimony is detail salience -- when a complex incident is witnessed, not all
the details are equally salient, or memorable, but in general, "the
extraordinary, colorful, novel, unusual, and interesting scenes attract our
attention and hold our interest."
As we now know, these factors are no less relevant to the eyewitness
testimony regarding the image of a planet.
Percival Lowell's lawyerly marshaling of evidence in favor of the
reality of the Martian canals and the civilization he deduced from their
presence is assembled in his books: Mars
(1895), Mars and its Canals (1906),
and Mars as the Abode of Life
(1908). In many ways, his arguments
seemed very convincing, but they all turned on the reliability of eyewitness
testimony: that of the man at the telescope.
"Professor Percival Lowell ... enrolled
[me] to observe Mars every night for nearly six weeks through his twenty-four
inch refractor.... Imagine my surprise and chagrin when I first saw the
beautiful disk of Mars through the superb telescope. Not a line! not a marking!..."
Eventually Morse
progressed in his ability to see the canals and added his testimony to that of
other eyewitnesses. In the courtroom,
the testimony of such eyewitnesses, says Loftus, "is likely to believed ... especially when it is offered with a high level
of confidence... All the evidence points
rather strikingly to the conclusion that there is almost nothing more
convincing than a live human being who takes the stand, points a finger at the
defendant, and says, 'That's the one!'"
Loftus mentions the
well-known case of the
in the 1920s. One
witness, Mary Splaine, positively identified Sacco, even though the murderers riding in a car passed no
closer to her than sixty feet and she had the car in view only for the period
it took the car to travel fifty or sixty feet:
"Q: ...The hand you said you saw
where?"
"A: The left hand, that was placed ...
on the back of the front seat. He had a
gray, what I thought was a shirt -- had a grayish, like navy color, and the
face was what we would call clear-cut, clean-cut face. Through here [indiciating]
was a little narrow, just a little narrow. The forehead was high. The hair was brushed back and it was between,
I should think, two inches and two-and-one-half inches in length and had dark
eyebrows, but the complexion was a white, a peculiar white that looked
greenish."
In commenting on Splaine's testimony, a psychologist said: "Such perception
and memory under such conditions can be easily proved to be pscyhologically
impossible. Every psychologist knows
that -- so does Houdini." {Felix Frankfurter, 1927. The
case of Sacco and Vanzetti.
Because of the
tremulousness of the air along the line of sight between the observer and Mars,
the red planet's disk becomes crystal-clear usually for only moments, fractions
of a second, at a time. It is in these
glimpses that
the perceptions, the eye and brain manage to record
only the most salient features (lines) Under these conditions, Lowell, Morse,
and other canalists were as unreliable in what they
reported than Splaine seems to have been.
It is widely conceded that Sacco and Vanzetti were falsely convicted for the
acquitted of haboring intelligent
life.
Bill SHEEHAN (