I do not mean to suggest that all of Velikovsky’s legendary concordances and ancient scholarship are similarly flawed, but many of them seem to be, and the remainder may well have alternative, for example diffusionist, origins.
With the situation in legend and myth as fuzzy as this, any corroboratory evidence from other sources would be welcomed by those who support Velikovsky’s argument. I am struck by the absence of any confirming evidence in art. There is a wide range of paintings, bas-reliefs, cylinder seals and other objets d’art produced by humanity and going back to at least 10,000 B.C. They represent all of the subjects, especially mythological subjects, important to the cultures that created them. Astronomical events are not uncommon in such works of art. Recently (Brandt, et al., 1974), impressive evidence has been uncovered in cave paintings in the American Southwest of contemporary observations of the Crab Supernova event of the year 1054, which was also recorded in Chinese, Japanese and Arab annals. Appeals have been made to archaeologists for information on cave painting representations of the earlier Gum Supernova (Brandt, et al., 1971). But supernova events are not nearly so impressive as the close approach of another planet with attendant interplanetary tendrils and lightning discharges connecting it to Earth. There are many unflooded caves at high altitudes, distant from the sea. If the Velikovskian catastrophes occurred, why are there no contemporary graphic records of them?
I therefore cannot find the legendary base of Velikovsky’s hypothesis at all compelling. If, nevertheless, his notion of recent planetary collisions and global catastrophism were strongly supported by physical evidence, we might be tempted to give it some credence. If the physical evidence is not, however, very strong, the mythological evidence will surely not stand by itself.
LET ME GIVE a short summary of my understanding of the basic features of Velikovsky’s principal hypothesis. I will relate it to the events described in the Book of Exodus, although the stories of many other cultures are said to be consistent with the events described in Exodus:
The planet Jupiter disgorged a large comet, which made a grazing collision with Earth around 1500 B.C. The various plagues and Pharaonic tribulations of the Book of Exodus all derive directly or indirectly from this cometary encounter. Material which made the river Nile turn to blood drops from the comet. The vermin described in Exodus are produced by the comet-flies and perhaps scarabs drop out of the comet, while indigenous terrestrial frogs are induced by the heat of the comet to multiply. Earthquakes produced by the comet level Egyptian but not Hebrew dwellings. (The only thing that does not seem to drop from the comet is cholesterol to harden Pharaoh’s heart.)
All this evidently falls from the coma of the comet, because at the moment that Moses lifts his rod and stretches out his hand, the “Red Sea” parts-due either to the gravitational tidal field of the comet or to some unspecified electrical or magnetic interaction between the comet and the “Red Sea.” Then, when the Hebrews have successfully crossed, the comet has evidently passed sufficiently farther on for the parted waters to flow back and drown the host of Pharaoh. The Children of Israel during their subsequent forty years of wandering in the Wilderness of Sin are nourished by manna from heaven, which turns out to be hydrocarbons (or carbohydrates) from the tail of the comet.
Another reading of Worlds in Collision makes it appear that the plagues and the Red Sea events represent two different passages of the comet, separated by a month or two. Then after the death of Moses and the passing of the mantle of leadership to Joshua, the same comet comes screeching back for another grazing collision with the Earth. At the moment that Joshua says “Sun, stand thou still upon Gibeon; and thou, Moon, in the valley of Ajalon,” the Earth-perhaps because of tidal interaction again, or perhaps because of an unspecified magnetic induction in the crust of the Earth-obligingly ceases its rotation, to permit Joshua victory in battle. The comet then makes a near-collision with Mars, so violent as to eject it out of its orbit so it makes two near-collisions with the Earth which destroy the army of Sennacherib, the Assyrian king, as he was making life miserable for some subsequent generation of Israelites. The net result was to eject Mars into its present orbit and the comet into a circular orbit around the Sun, where it became the planet Venus-which previously, Velikovsky believes, did not exist. The Earth meantime had somehow begun rotating again at almost exactly the same rate as before these encounters. No subsequent aberrant planetary behavior has occurred since about the seventh century B.C., although it might have been common in the Second Millennium.
That this is a remarkable story no one-proponents and opponents alike-will disagree. Whether it is a likely story is, fortunately, amenable to scientific inquiry. Velikovsky’s hypothesis makes certain predictions and deductions: that comets are ejected from planets; that comets are likely to make near or grazing collisions with planets; that vermin live in comets and in the atmospheres of Jupiter and Venus; that carbohydrates can be found in the same places; that enough carbohydrates fell in the Sinai peninsula for nourishment during forty years of wandering in the desert; that eccentric cometary or planetary orbits can be circularized in a period of hundreds of years; that volcanic and tectonic events on Earth and impact events on the Moon were contemporaneous with these catastrophes; and so on. I will discuss each of these ideas, as well as some others-for example, that the surface of Venus is hot, which is clearly less central to his hypothesis, but which has been widely advertised as powerful post hoc support of it. I will also examine an occasional additional “prediction” of Velikovsky-for example, that the Martian polar caps are carbon or carbohydrates. My conclusion is that when Velikovsky is original he is very likely wrong, and that when he is right the idea has been pre-empted by earlier workers. There are also a large number of cases where he is neither right nor original. The question of originality is important because of circumstances-for example, the high surface temperature of Venus-which are said to have been predicted by Velikovsky at a time when everyone else was imagining something very different. As we shall see, this is not quite the case.
In the following discussion, I will try to use simple quantitative reasoning as much as possible. Quantitative arguments are obviously a finer mesh with which to sift hypotheses than qualitative arguments. For example, if I say that a large tidal wave engulfed the Earth, there is a wide range of catastrophes-from the flooding of littoral regions to global inundation-which might be pointed to as support for my contention. But if I specify a tide 100 miles high, I must be talking about the latter, and moreover, there might be some critical evidence to counterindicate or support a tide of such dimensions. However, so as to make the quantitative arguments tractable to the reader who is not very familiar with elementary physics, I have tried, particularly in the Appendices (following the References), to state all the essential steps in the quantitative development, using the simplest arguments that preserve the essential physics. Perhaps I need not mention that such quantitative testing of hypotheses is entirely routine in the physical and biological sciences today. By rejecting the hypotheses that do not meet these standards of analysis, we are able to move swiftly to hypotheses in better concordance with the facts.
There is one further point about scientific method that must be made. Not all scientific statements have equal weight. Newtonian dynamics and the laws of conservation of energy and angular momentum are on extremely firm footing. Literally millions of separate experiments have been performed on their validity-not just on Earth, but, using the observational techniques of modern astrophysics, elsewhere in the solar system, in other star systems, and even in other galaxies. On the other hand, questions on the nature of planetary surfaces, atmospheres and interiors are on much weaker footing, as the substantial debates on these matters by planetary scientists in recent years clearly indicate. A good example of this distinction is the appearance 1975 of Comet Kohoutek. This comet had first been observed at a great distance from the Sun. On the basis of the early observations, two predictions were made. The first concerned the orbit of Comet Kohoutek-where it would be found at future times, when it would be observable from the Earth before sunrise, when after sunset-predictions based on Newtonian dynamics. These predictions were correct to within a gnat’s eyelash. The second prediction concerned the brightness of the comet. This was based on the guessed rate of vaporization of cometary ices to make a large cometary tail which brightly reflects sunlight. This prediction was painfully in error, and the comet-far from rivaling Venus in brightness-could not be seen at all by most naked-eye observers. But vaporization rates depend on the detailed chemistry and geometrical form of the comet, which we know poorly at best. The same distinction between well-founded scientific arguments, and arguments based on a physics or chemistry that we do not fully understand, must be borne in mind in any analysis of Worlds in Collision. Arguments based on Newtonian dynamics or the conservation laws of physics must be given very great weight. Arguments based on planetary surface properties, for example, must have correspondingly lesser weights. We will find that Velikovsky’s arguments run into extremely grave difficulties on both these scores, but the one set of difficulties is far more damaging than the other.