astrology

Don't expect a comprehensive account of astrology here, I wouldn't want to get bogged down that much. Astrology is ancient and no doubt many branched and possibly internally riven. As I sit down to write this, I confess that I know little about it beyond the claim that stars and their movements and relations somehow affect the character of humans [and presumably also koalas and stick insects, but we don't so much care about them] on this planet, and that these influences are related to signs of the zodiac, cusps, risings and ascendants. I'm also pretty sure that there's no real testable, verifiable mechanism to explain these influences and effects, though there's always been a lot of talk, of a more or less serious nature, about so-and-so being a typical gemini, leo or whatever. I've always considered astrology to be pure bullshit just on a prima facie basis, without feeling the need to investigate further. After all, if it were true that our stars largely form our character, we would be able to use such knowledge to slot people into their rightful or most fruitful places in society, a la Plato's Republic. But of course I also know that astrological ascriptions of character are so notoriously vague as to be unfalsifiable. I myself am a 'cancer', described as sensitive, artistic and home-loving. I can barely think of anyone who couldn't be tweaked to fit that description, from Jesus to Hitler. There is actually a useful term for this - the Forer effect.
So, is there more to astrology than these vagueries, and why is it so god-damned popular?

Wikipedia has a painfully lengthy article on the subject, and early on they make this interesting remark:

Few astrologers believe that the movements and positions of celestial bodies either directly influence life on Earth or correspond to events experienced on a human scale. More common is the idea that astrology is a symbolic language, an art form, or a form of divination.

They're talking no doubt about modern, western astrologers. The idea is that modern astrologers know better than to make large, testable claims they won't get away with, better to retreat to the byways of 'art' or 'divination'. Unfortunately this retreat from a mechanism by which the celestial influences the terrestrial just won't work. Like theology, there just has to be something at the heart of it, though maybe not, for astrology has affinities with theology in that labyrinthine arguments can be developed out of the skein of the human mind, on the flimsiest of pretexts, when some kind of perceived self-interest is involved - though to me the self-interest in astrology is less clear than the self-interest in theology. That might seem silly in that, in one sense, it's clear that astrology is less about stars and zodiacs than it is about us, but astrology almost seems like mystification for its own fun sake, whereas theology is more clearly about a god who makes us specially and therefore makes us special. 
Anyway, I'm not sure how astrology can be classified as an art, as it has no clear aesthetic dimension. And I don't know how you can determine that someone is good at the art. If you think of the art of violin-making, for example, the product will be a really fine violin, supposing the maker to be a true artist. Fine violins are measurable in their fineness. I presume that with astrologers, the measure of their art is the success of their divinations. What else could it be? Surely not their beauty or richness. The richness of their divinations would only be significant if they came true - everything hangs on that.
So when the success of an activity depends on results  - think of medicine, or science in general [the question of whether or not psychology is a science is really a question of whether it produces results in the form of cumulative knowledge, as biology and physics have] - it's slightly ridiculous, it seems to me, to retreat to the claim that it's really an art.
Astrology is of course more ancient than astronomy. In fact, last year marked what some described as the 400th anniversary of astronomy's birth, when Galileo trained a telescope upon the heavens. Of course this is an insult, not only to Copernicus and the many other pioneers immediately preceding Galileo, but to Ptolemy and the many other ancients who used the heavens to produce real knowledge. But it's largely only in the modern era that the stars were examined for their own sakes rather than for ours. Astrology is a typical product of those pre-scientific times it seems to me.
I'm not going to provide an account of the historical development of the various branches and cultural traditions in astrology here - you'll find much of that in the above-mentioned Wiki article and at many other sites, including this sceptical one. Suffice to say that they were valuable traditions in that they represent the fruits of our first obsessions with the behavior of the stars. I'm sure that the first genuine theorists about what was out there gleaned much from the painstaking records of the early astrologers. Interesting to note, though, that astrology was to some degree driven underground by the spread of Christianity - the 'intervention' of the stars no doubt being seen as devilishly competing with divine intervention. This quote from Johannes Kepler at the very beginning of the scientific renaissance provides an interesting example of the half-Christian, half-scientific negativity towards astrology:

"It should not be considered unbelievable that one can retrieve useful knowledge and sacred relics from astrological folly and godlessness. From this filthy mud one can glean even an occasional escargot, oysters or an eel for one's nutrition; in this enormous heap of worm-castings there are silk-worms to be found; and, finally, out of this foul-smelling dung-heap a diligent hen can scratch up an occasional grain-seed -- indeed, even a pearl or a gold nugget."

Sometimes astrologers make a half-hearted attempt to associate a mechanism for astrological influence with the well-known tidal effects of the moon. Of course this is absurd for many reasons. Gravitational effects diminish very precisely with the square of the distance between two bodies, and with stars other than the sun, the distances are ginormous, though the objects may be very massive. I don't think mass and distance are much taken into account anyway in astrology. Also, tidal effects occur only with oceans, bodies of water which cover significant regions of the surface of the earth. They don't occur with small bodies of water, nor do they occur with people [and we're only talking about tidal effects, never mind the personality effects claimed]. Of course there's the age-old claim that the moon, especially the full moon, has a definite effect on people's behaviour, including the inducing of madness [lunacy]. However, the vast majority of carefully conducted studies indicate that this belief is a myth - but I'm going off topic.
To finish off, the onus is and always has been upon astrologers that their field is about something. In this it's in a similar position to theology. Astrologers, in defending their turf against the analyses of empiricists, argue that the field is incredibly complex, so that all known tests inevitably miss something - usually something incredibly vital. Basically, they're arguing that the field is untestable, usually the first sign of a pseudoscience. It seems to me, though, that all the talk of ascendants, descendants, cusps and houses only obscures the central issue - how can these celestial bodies influence human behaviour? That simple, central question is never answered, and is usually never even addressed. The same problem applies to theology. The constant elaboration of the properties or essence of the deity obscures rather than clarifies the central question - what evidence is there for a supernatural mechanism causing natural events? What lies at the centre of astrology, and theology, is not a mechanism but a massive, untestable assumption.

contumely

a master of contumely, inevitably evoking contumelious rejoinders

This one's a request, and it takes me back to my early days when I read lots of Victorian lit. Contumely is, surprisingly, a noun, and some of its synonyms are abuse, vituperation [a word I still actually use], invective and vitriol. It was quite popular in the nineteenth century [Hawthorne used it] though probably even more so in earlier centuries. Here's an example from Francis Bacon's essay 'Of Superstition':

IT WERE better to have no opinion of God at all, than such an opinion, as is unworthy of him. For the one is unbelief, the other is contumely; and certainly superstition is the reproach of the Deity. Plutarch saith well to that purpose: Surely (saith he) I had rather a great deal, men should say, there was no such man at all, as Plutarch, than that they should say, that there was one Plutarch, that would eat his children as soon as they were born; as the poets speak of Saturn. And as the contumely is greater towards God, so the danger is greater towards men. Atheism leaves a man to sense, to philosophy, to natural piety, to laws, to reputation; all which may be guides to an outward moral virtue, though religion were not; but superstition dismounts all these, and erecteth an absolute monarchy, in the minds of men.

I chose this one not just for the usage, but for the mention of atheism, though I'm not sure that I can clearly make out Bacon's meaning. I mean the first sentence is clear enough, and the first half of the second, but what is meant by 'superstition is the reproach of the deity'? Presumably he means that superstition misinterprets the deity, imputing to him/her/it diabolical intent, as in the example of Saturn. Better to be an atheist than to be superstitious about gods, Bacon apparently believes. It's an interesting passage [and the continuation is interesting too] in that it really seems an early defence of atheism, but I don't believe that, as some claim, Bacon was an atheist.

Returning to contumely, the obnoxious Mr Knox, who still has his fans today, used the word himself in this typical quote from his eternally veritable 'First Blast of the Trumpet Against the Monstrous Regiment of Women':

And therefore yet again I repeat that which before I have affirmed: to wit, that a woman promoted to sit in the seat of God, that is, to teach, to judge or to reign above man, is a monster in nature, contumely to God, and a thing most repugnant to His will and ordinance. For He hath deprived them as before is proved of speaking in the congregation and hath expressly forbidden them to usurp any kind of authority above man.

Knox was of course reacting to the awful fact that a woman was then sitting on the throne of Scotland, and another on the throne of England, at a time when ordinary women rightfully had no rights at all to speak of. Truly a world turned upside down.
Contumely comes from Old French, contumelie, which is in turn derived from the Latin contumelia, a reproach or insult. It's probably related also to the Latin contumax [haughty, stubborn]. Con- as a prefix is an intensifier, and tumere means to swell up [think of the various tumescences Fanny Hill had to deal with].

gastrulation

Recently I read about the biologist Lewis Wolpert. He apparently attained some notoriety years ago when he declared: 'It is not birth, marriage, or death, but gastrulation which is truly the most important time in your life.' Wow, I'd never heard of gastrulation, in spite of being I hope a little more educated on matters biological than most punters, which probably isn't much. So here I am writing and learning about gastrulation.
The first five letters of this word are familiar. Think of gastric ulcers, gastric juices, gastro-enteritis and you think of the stomach, right? Well, maybe. Later we'll have a quick look at etymology.
Gastrulation is a term for a very early phase of embryonic development, in humans as well as in fish, birds, frogs and sea urchins. And a few other creatures. Not surprisingly, gastrulation is complex, and the process varies for different species. I don't feel too confident about being able to explain it, but I'll try.
I'll focus on human gastrulation, because I'm only human. An egg becomes fertilized by a sperm cell in the fallopian tube, and the resultant combo, or diploid, is called a zygote [I'm going back a little way, to help put gastrulation in its context in the development of the embryo]. By the way, the two cells that unite in sexual reproduction to form a zygote are called gametes, and apparently, where the two sexes produce morphologically distinct gametes [as in humans] the female is defined as the one who produces the larger gamete, the egg or ovum. Presumably this is the same for all mammals, and maybe for all sexually reproducing species, and perhaps if we have a species where both sets of gametes are the same size, you wouldn't be able to tell the male from the female of that species? Just speculating.
Anyway, gametes are haploid cells, that is they have half the number of chromosomes as a diploid cell. Once the two gametes have fused to form a diploid zygote [fertilization or conception], the zygote 'cleaves' to form a ball of cells [all diploid cells] called a morula. At this point the cells remain undifferentiated. They're called blastomeres. All of these stages of development, and each of the new words here mentioned - morula, blastomere, cleavage [in the boringly non-Partonesque sense] - could have a separate essay, or a book, dedicated to them, but I'll slide over them for now or I'll never see my way clear to gastrulation. Meanwhile here's a picture to help us with the very early phases of human embryo development.

The morula [about 16 cells] soon transforms into a blastula [day 5 above], consisting of a single layer of parietal [outer] cells and a blastocoelic cavity. Implantation, or attachment to the uterine wall, takes place on the seventh day [probably prophesised in the Bible, given a bit of stretching]. More accurately there's a period known as the human implantation window, which is 6 to 12 days.
The formation of the blastula from the morula, called blastulation, begins the process of cell differentiation. Somehow the undifferentiated cells become two different types of cell, the trophoblasts which form the wall of the blastocyst [as it's called in mammals], and an inner mass of cells called embryoblasts, from which, by the way, embryonic stem cells are taken. Here's an illustration of a blastocyst a little before implantation.

The trophoblasts combine with the maternal endometrium cells to form the placenta in eutherian [placental] mammals. The human blastocyst is made up of 70 to 100 cells, according to Wikipedia, whereas at this site, the pre-implantation human embryo [which is only a blastocyst] contains 200 to 250 cells. What is a dilettante to think? That second site, to be precise, is the 'web-book' Introduction to Developmental Biology, by Frank Lee. 

Anyway, now we come to gastrulation proper. In brief, it's the phase in which the blastocyst generates three germ layers, the ectoderm, mesoderm and endoderm, but this explains nothing. Germ layers are essentially germinal of tissue layers, producing all the tissues and organs of the body. 

What happens first is that the embryoblasts differentiate into hypoblasts and epiblasts. The culumnar epiblast cells give rise, finally, to the three germ layers leading to organs and tissues, while the cuboidal hypoblasts are the originators of  the cells of the yolk sac and the extraembryonic endoderm, that's to say the stuff inside the sac, I think. Actually the shape of the cells varies with species. Within the blastocyst, the epiblasts form adjacent to the trophoblast, while the hypoblasts are closer to the blastocoel. 

The development from blastula to gastrula involves amongt other things the formation of a structure called the primitive streak, which establishes bilateral symmetry, determines the site of gastrulation and initiates the formation of germ layers. What happens is that mesenchymal cells, or embryonic connective tissue cells, line up along the long axis of an elongating blastocyst, creating a prospective midline. This is described as the first symmetry-breaking event in the development of the embryo [I've also been reading about symmetry-breaking in cosmology, so that's interesting]. Cells move along and around the primitive streak in a constant flow. There are two counter-rotating flows that meet at the posterior of the streak. 

My primitive research is still sufficient for me to recognize that the formation of the primitive streak is a complex matter indeed, so I won't get into it here, I'll only get lost in the labyrinth. Interestingly, some bioethicists argue that the formation of the primitive streak [at about the fourteenth day in humans] signifies the creation of a unique, truly human being, presumably through some abstruse argument based on differentiated cell development. On the face of it, this seems another example of the crudity of discontinuous thinking, bemoaned by the likes of Richard Dawkins.

Here's one of the best simple summaries of gastrulation I've found, from UNSW embryology:

Gastrulation means "gut forming" and converts the inner cell mass which then formed the bilaminar embryo (epiblast, hypoblast) into the trilaminar embryo (ectoderm, mesoderm, endoderm).

The process involves the migration of cells from the epiblast layer through the primitive streak to form first the endoderm layer and then a second intermediate layer the mesoderm layer. Once all cells have left the epiblast layer it now becomes the ectoderm layer.

These three germ cell layers (ectoderm, mesoderm, endoderm) will form in a layer specific manner all the future tissues of the developing embryo.

The term itself goes back to the 1870s.  

This is as far as I'm going to go with gastrulation. I've certainly learnt a lot about embrology that I didn't know before, and I'll definitely make a return some time with more embryological terms.

introduction [not the word]

Taking a break from too much scepticism, I've hit upon this bright idea of writing about words, though not just any words, words that I can get my teeth into and use to learn about the world, to plug one or two of the billions of holes in my knowledge. Many of the words will be science-words, and will help me open up the world of physics and biology and so on just a little bit more for myself. Some might be philosophical, or esoteric, or controversial, and some may be worth writing whole books upon, but I won't be doing that.

I suppose the main point is that this will not be a blog primarily dealing with linguistics, etymology or philology [a sadly out-of-date term these days]. It's not the words that interest me so much as the things or processes they describe. It's my way of burrowing into these things and processes, in some small degree.

Since I don't have a readership, mea culpa, I'll dedicate this blog to the future, in the form of an eight-year-old girl named Courtney. And if anybody else stumbles upon this blog and derives any pleasure or stimulation from it, well and good, and please leave a comment.