I don’t seem to have provoked anyone for quite sometime, so I thought I would set up a quick Hist_Sci Hulk triple threat match before I disappear off on holiday. What follows are three things that irritated me on the Internet in recent days.
The major scientific theme of the day has been, of course, Monday’s total eclipse over America. In the lead up we have seen a lot on the Internet about eclipse maps. Eclipse maps are maps that show/predict the shadow path of the eclipse usually differentiating between those areas experiencing a full eclipse and those only experiencing various degrees of partial eclipse. On 17 August the website Atlas Obscura had an article on eclipse maps with the title How Edmond Halley Kicked Off the Golden Age of Eclipse Mapping that featured Halley’s 1715 eclipse map. Now this title contains a serious history of astronomy error and Atlas Obscura were unfortunately not the only ones to make it in the lead up to Monday’s great solar event.
Edmond Halley did not kick off the Golden Age of Eclipse Mapping, the seventeenth-century mathematician and astronomer Erhard Weigel (1625–1699) (who you can read about here) did with an eclipse map published in 1654 sixty-one years before Halley’s effort.
Halley wasn’t even second in the eclipse map stakes as Weigel’s student Johann Christopher Sturm (1635–1703) (who you can read about at the Weigel link) published one 1676, thirty-nine years before Halley.
Both Weigel and Sturm were known to the Royal Society, of which Halley was both a member and for a time an employee, and Sturm was also a member, so there is a strong possibility that Halley knew of the efforts of his German colleagues and cannot even be regarded as an independent inventor.
If you want all of the dope on eclipse maps then I highly recommend the excellent Eclipse-Maps website, which can fill all of your eclipse map desires whatever they might be. It is the source of the three eclipse maps shown here.
Another eclipse related false claim is the one presented below:
Now Ibn al-Haytham (c.965–c.1040) is one of the most important figures in the history of optics and he put the pinhole camera effect to very good use in his optical researches but he can’t be said to have invented it. You don’t actually have to build a ‘camera’ to display the pinhole camera effect and there are plenty of images on the web of people projecting images of the eclipse onto some sort of background through a hole in a hat, through a colander, through the holes in a salt cracker etc., etc.
The earliest known description of the pinhole camera effect can be found in the so-called Chinese Mozi writings, which date from the fifth century BCE, so about one and a half thousand years before Ibn al-Haytham lived. A description of the pinhole camera effect can also be found in the writings of Aristotle (384–322). In his Problems Aristotle wrote:
Why is it that an eclipse of the sun, if one looks at it through a sieve or through leaves, such as a plane-tree or other broadleaved tree, or if one joins the fingers of one hand over the fingers of the other, the rays are crescent-shaped where they reach the earth? Is it for the same reason as that when light shines through a rectangular peep-hole, it appears circular in the form of a cone?
As you can see he’s even describing using the effect to view a solar eclipse. As a small bonus, the name camera obscura for the pinhole camera (the origin of the term camera) was coined by Johannes Kepler.
My third rant of the day leaves the direct field of history of science and moves into the sphere of science communication and philosophy of science. Also provoked by the eclipse several different versions of the following meme have been circulating in the Internet over the last few days. I don’t know who originated it but Neil deGrasse Tyson has been aggressively tweeting a shorter version.
Now I’m a one hundred per cent supporter of science and the scientific method (whatever that might be) and the results that they produce in their attempts to explain our world but I find the analogy drawn here simplistic, naive and anything but helpful. I will endeavour to explain my thoughts on the matter.
Put very simply people are making the mistake here of comparing apples with oranges. A solar eclipse and its scientific explanation are of a very different type to the science of evolution or vaccines and all the other things that denialists reject.
First of all there is a time dimension. Already in the second half of the first century BCE Babylonian astronomers were pretty good at explaining solar and lunar eclipses and could predict lunar ones accurately and at least predict when a solar eclipse could theoretically take place. This knowledge was acquired through many centuries of astronomical observation. So, we are talking about more than two thousand years for people to digest and accept the science behind solar eclipses. In contrast to this, the theory of evolution and the scientific explanation for vaccines are both products of the nineteenth century and less than two hundred years old, far less time for people to digest and accept.
The second factor and the more serious one is complexity. Once you accept that the sun, the moon and the earth are just three balls rotating through the heavens, something accepted in Europe around five hundred BCE, – whether your model is geocentric or heliocentric doesn’t make any real difference to the explanation – then the scientific explanation of an eclipse is, to put it mildly, trivial. In fact it can be easily demonstrated in any classroom using a powerful torch (that’s a flashlight for Americans), a basketball and a large inflatable terrestrial globe. I’ve even seen it demonstrated using a torch and three children as the sun, the moon and the earth. There is not an awful lot you have to understand.
If we now turn to evolution or vaccines we are in a wholly different ball game. The theory of evolution is a highly complex scientific theory based on a vast amount of scientific material. The same can be said of the science behind the theories of disease and the use of vaccines to combat some of them. These are not scientific results that can be lucidly explained by a simple classroom demonstration in a couple of minute.
A third factor is personal involvement. There is a certain distance between a human being and the object of astronomy. It is true that we are dependent on the sun for our existence but on the whole we don’t connect to celestial objects on a very personal level. Things are very, very different with both the theory of evolution and vaccines. The theory of evolution says very directly where we as a species come from and that people have difficulty getting their heads around the fact that we are, over a long period of time, descended from some sort of proto-ape-like creature, in fact from the very same proto-ape-like creature as chimpanzees and gorillas shouldn’t come as a surprise. Remember that infamous Victorian quip, “You might think that your grandfather was an ape, sir but your grandmother!” It’s very easy to mock but it’s a hell of a long stretch to convince people to believe the theory of descent. Add to this the complexity of the actually mechanisms of evolution and that you are going to have problems convincing people to accept them shouldn’t surprise anybody.
All the above can be repeated for the theory of disease and the explanations for the function of vaccines; it’s all very, very complex and difficult to swallow for many people. Add to this the fact that vaccine damage is a reality. Before anybody tries to teach me how to suck eggs, I am well aware of the fact that the risk of any given child suffering vaccine damage is by several factors lower than the risk of death or serious brain damage, from say measles, for a child in a non-vaccinated population. But this statement has two problems, firstly ‘my child’ could be damaged by the vaccine, people are emotional, and secondly people don’t understand statistics. Any scientific explanation that involves statistics is likely to set the recipient in a state of panic.
As science communication, or spreading the science gospel, I find the meme above underwhelming to say the least. To say in an arrogant, sneering tone that if you accept the scientific explanation for, trivial phenomenon, A then you have to accept the scientific explanation for, anything but trivial, B is in my opinion anything but helpful and is more likely to antagonise than convince.