Jim Hoffman updates Mackey critique at 911research.wtc7.net

Maintaining the Mirage: A Foray Into the Fallacy Factory of the Demolition Deniers

A critique of Ryan Mackey's essay: "On Debunking 9/11 Debunking: Examining Dr. David Ray Griffin's Latest Criticism of the NIST World Trade Center Investigation"

by Jim Hoffman - Version 0.9; May 18, 2008

"Someone reading just the Introduction or Discussion of Mackey's 180-page article might easily conclude that that the entire article is composed of insults, straw-man arguments, innuendo, and appeals to authority. However, the article contains a range of types of arguments, from the obviously falacious ones to cleverly misleading ones to superficially persuasive ones having some didactic value. This review will put Mackey's arguments in context, reframed by the physical reality of the event.

For this critique I use an organization that departs from both that of Griffin's chapter and Mackey's article, in order to bring the focus back to the core issue: what caused the swift and total destruction of the World Trade Center. Mackey's long-winded article, like most reviews professing to debunk the case for controlled demolition, conceals that issue by redirecting readers into a bottomless well of exaggerated details and a variety of fallacies that depart ever further from the core evidence that speaks to the question at hand.

This review first outlines a series of arguments for controlled demolition, examining arguments by Mackey in relation to those arguments; then provides a "global analysis" of Mackey's methods. This organization is intended to extract Mackey's substantive and relevant arguments from his abundant unsupported and gratuitous assertions and characterizations regarding Griffin's work, and to highlight and address those arguments..."


Needs to be better proofed

The linked article has a lot of typos and editing errors. Hoffman or an assistant should carefully read through the whole thing and fix them.


Thanks for the reminder -- corrections are in process with a member of the team.

Ronald Wieck on Air America...

Last week, during Richard Greene's "Week of Truth Episode 3," the one "debunker" who was willing to be the guest defending the official story accused the truth movement of not addressing arguments that contradict our claims. He said, in supporting his absurd contention that Griffin is intentionally lying in order to sell books: "NASA scientist Ryan Mackey has done a whitepaper, available online, which systematically destroys Griffin's arguments. Griffin has not answered Mackey."

This might lead people to believe that NO ONE has answered Mackey, as is clearly not the case:


The above is Kevin Ryan's answer to Mackey.


The above is C. Thurston's response to Mackey.

Both in addition to the outstanding work of Mr. Hoffman. As I said on another comment thread, debunkers' presence should really be ignored unless they get in your face and you have to shoo them away, as these papers do very well. Great job folks.

The MacArthur overpass

First, I'd like to quote Hoffman here on this subject:

" 'A third example, occurring after Dr. Griffin’s manuscript was finalized, is the collapse of the Interstate 580 overpass in the MacArthur Maze near San Francisco. This overpass, supported only by steel beams, suffered no impact but collapsed due to the heat of an 8,600 gallon gasoline fire, burning in the open below, after nineteen minutes.' [quoting Mackey] p.12-13

"Mackey's third example is often cited as supporting the official story of the WTC collapses, as if the fire-induced collapse of a viaduct section (of which there are a number of examples) lends plausibility to the fire-induced collapse of a skyscraper (of which there are no examples).

"But let's assume there is some basis for comparison. Consider that the collapsed span of the MacArthur Maze fell, unimpeded, through about 20 feet of space before being brought to a complete halt by the elevated roadway below it, even though that roadway was not designed to support the upper span, even under static conditions. Compare that to the explanation of the Towers' collapse in which the upper sections, after falling through about 10 feet of space occupied by columns that would have to be crushed, proceeded to crush the rest of Towers all the way to the ground, all the way destroying columns designed to support the static loads of the upper portions.

"Aside from these fundamental differences, there are vast differences in the scales of the supposed causes and observed outcomes of the WTC and Maze events. The alleged causes would be more comparable had the Towers been hit by jumbojet tankers carrying eight times as much fuel as the 767s, and the fires were fully ventilated by the removal of all windows throughout 10-floor regions. The outcomes would be more comparable had the collapse of the Maze span triggered the total collapse of the numerous undamaged viaducts throughout the 30-acre MacArthur Maze."

I live in the East Bay (the east-central expanse of the San Francisco Bay Area), where the MacArthur Maze is located, so I notice the collapse there as something still on many minds.

Hoffman's discussion here throws me off. He says that "viaduct section[s]" have collapsed before but suggests that has no bearing on skyscrapers, with no further elaboration. (The rest of the discussion, which I've never heard before but which makes some excellent points, describes how the effect of the overpass collapse fails as an analogy to the WTC pseudo-collapses.)

Lacking an engineering background, I looked in a dictionary which defines "viaduct" as "1. a long bridge consisting of a series of short concrete or masonry spans supported on piers or towers, usually to carry a road or railroad over a valley, gorge, etc. 2. a similar structure of steel girders and towers." (Webster's New World Dictionary, 1974.)

What I'm getting at is Hoffman doesn't explain what it is that accounts for the collapse of the freeway overpass that's so unlike a steel-frame skyscraper. Rather, he talks around it, finally emphasizing how the collapse of a single span didn't have the effect on surrounding structures that might otherwise render it analogous to the WTC skyscraper holocaust -- good comparison, but nonexplanatory. One might even get the impression that Hoffman doesn't have a firm grasp on why the overpass collapsed.

Last year I attended Richard Gage's multimedia presentation, held in the East Bay. During Q-&-A, someone asked about the MacArthur collapse. Gage's answer was short and to the point (too bad he hadn't simply incorporated it into his lecture):

The overpass was not a steel-frame structure. Instead, it was a concrete structure (though it had iron reinforcement rods embedded in it). Concrete -- though this might seem counterintuitive to the layman -- tends to crack apart when heated much. Indeed, that's one of the primary reasons skyscrapers have to be steel-frame: to assure against global collapse in the event of a large fire.

Now maybe I've got things wrong here, about Hoffman or Gage. I certainly don't know civil engineering, and just trying to put down words about the subject feels awkward. Do others have thoughts about this?

a few points

>>What I'm getting at is Hoffman doesn't explain what it is that accounts for the collapse of the freeway overpass that's so unlike a steel-frame skyscraper.

Concrete and steel frame structures are fundamentally different in how they perform, both under normal and fire conditions. This isn't that hard to imagine. We don't see skyscrapers in NYC built from concrete for many reasons. Concrete structures *do* collapse from fire, unlike steel. And the fire was different and in the open air -- they just stood there and watched it burn continuously for hours, a fire that had a whole tank of fuel to feed it.

For me the key point made here is that undamaged structures should never collapse to the ground when damaged sections fall on them no matter what they are made of -- the highway below did not collapse even though the whole section above fell on it. Yet we are to believe that the WTC towers could not hold the small upper sections. This is key. There is no reason for any undamaged structure to fail.

>>One might even get the impression that Hoffman doesn't have a firm grasp on why the overpass collapsed.

Actually he does. It's unclear to me why you need this spelled out to the letter when you seem to have the same basic understanding as most do.

I live in the East Bay too, followed the story as it happened and progressed, and had no trouble with understanding why the collapsed section did collapse. I'm not sure what the specific detail is you are looking for. Jim's writing on this makes sense to me.

Let me try again

Hoffman doesn't say, in my reading of him, how it came about that the viaduct structure of the overpass collapsed from fuel-driven fire, even as steel-frame skyscrapers never collapse from liquid fuel-driven fire.

The fact that the overpass fire was open-air is noteworthy and doubtless contributed to the intensity of the fire, but Gage's comments suggest to me that that probably still wasn't enough to have caused the overpass collapse but for the fact that it was made from reinforced concrete instead of having been formed as a steel-frame structure.

I already mentioned how it is that the lower pass didn't pancake too is an excellent point in its own right -- which implicitly argues against the official pancaking theory of the WTC.

But my central point was narrower: Hoffman doesn't say why the overpass collapsed at all. Since the overpass was mainly concrete, the explanation -- which Hoffman bypassed, but which Gage stated upfront when asked -- is: Concrete cracks and fails when it gets above a few hundred degrees Fahrenheit. But because the WTC skyscrapers were steel-frame, there shouldn't have been any significant collapse at all (beyond the immediate effects of the jet impacts), as _they_ need to reach two thousand degrees or so to weaken significantly.

Narrow though though this is, it seems to me a crucial causal link in the chain of events being compared: The MacArthur overpass was made from something that by its nature collapses when held to normal flame, whereas the WTC skyscrapers were made from something that doesn't do that.

I'm not trying to pick on Hoffman, who's a superlative researcher and analyst and has contributed invaluably to our movement. I'm merely saying he missed an opportunity to make his passage about the MacArthur overpass stronger and more to the point.