Velikovsky's ideas have been almost entirely rejected by mainstream academia (often vociferously so) and his work is generally regarded as erroneous in all its detailed conclusions. Moreover, scholars view his unorthodox methodology (for example, using comparative mythology to derive scenarios in celestial mechanics) as an unacceptable way to arrive at conclusions. Stephen Jay Gould[33] offered a synopsis of the mainstream response to Velikovsky, writing, "Velikovsky is neither crank nor charlatan—although, to state my opinion and to quote one of my colleagues, he is at least gloriously wrong... Velikovsky would rebuild the science of celestial mechanics to save the literal accuracy of ancient legends."
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The fundamental criticism against this book from the astronomy community was that its celestial mechanics were physically impossible, requiring planetary orbits that do not conform with the laws of conservation of energy and conservation of angular momentum.
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Earlier in 1974, James Fitton published a brief critique of Velikovsky's interpretation of myth (ignored by Velikovsky and his defenders) whose indictment began: "In at least three important ways Velikovsky's use of mythology is unsound. The first of these is his proclivity to treat all myths as having independent value; the second is the tendency to treat only such material as is consistent with his thesis; and the third is his very unsystematic method."
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More recently, the absence of supporting material in ice-core studies (such as the Greenland Dye-3 and Vostok cores) has removed any basis for the proposition of a global catastrophe of the proposed dimension within the later Holocene period. However, tree-ring expert Mike Baillie would give credit to Velikovsky after disallowing the impossible aspects of Worlds in Collision: "However, I would not disagree with all aspects of Velikovsky's work. Velikovsky was almost certainly correct in his assertion that ancient texts hold clues to catastrophic events in the relatively recent past, within the span of human civilization, which involve the effects of comets, meteorites and cometary dust.... But fundamentally, Velikovsky did not understand anything about comets.... He did not know about the hazard posed by relatively small objects.... This failure to recognize the power of comets and asteroids means that it is reasonable to go back to Velikovsky and delete all the physically impossible text about Venus and Mars passing close to the earth.... In other words, we can get down to his main thesis, which is that the Earth experienced dramatic events from heavenly bodies particularly in the second millennium BC
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While James credits Velikovsky with "point[ing] the way to a solution by challenging Egyptian chronology", he severely criticised the contents of Velikovsky's chronology as "disastrously extreme", producing "a rash of new problems far more severe than those it hoped to solve" and claiming that "Velikovsky understood little of archaeology and nothing of stratigraphy."