I'm thinking the major piece missing from the statement is that yes, physical things have physicality and limitations (with limitality) but for the rest to follow then it assumes that all observations of physical things must, and do, perfectly represent their physicality and limitations.
Even a pancake earth or a disc earth has (1) a 'geometry', (2) a 'physicality' (since neither pancakes nor discs qualify as having a 'spirituality'
which would be the alternative to 'physicality') and (3) 'physical limitations' owing to geometry. In other words, Oakley is redefining otherwise commonly understandable terms in an unusual, selective and self-contradictory way in order to make his point.
To recap Oakley's problem: Oakley's usage of modus tollens
(MT is a valid inference rule in formal logic) is logically correct
but scientifically nonsensical
. If it were so simple that P
(the earth's average radius) automatically implies the Q
that no observer should ever observe even the slightest deviation from a geometric horizon (effectively ignoring the effects of atmospheric refraction, spheroid earth, etc.), Oakley would be absolutely correct insofar as demonstrating there's something wrong with the earth's radius hypothesis.
Since, indeed, there are
such deviations all the time, and which he calls 'black swans', something's wrong with the globe theory according to the above simplistic reasoning. His appeal to MT and black swans are all part of his 'sciency' veneer, making something ridiculous sound reasonable and intellectual to the uninitiate.
However, he's obviously blatantly wrong on both counts which his 'scienciness' fails to cover up: (1) Earth's geometric radius is not
perfectly symmetric even geometrically (earth is a spheroid rather than a sphere) (2) nor
does the human observer ever eyeball the exact geometric horizon due to atmospheric refraction.
That's why I earlier said that the bottom line here is the false and Dunning-Krugery (read: presumptuous) assertion that the globe theory cannot tolerate even the slightest variation from Oakley's simplistic application of MT in order for it to be true
P.S. In actual science modus tollens
is indeed a very important logical rule which allows the scientist to infer observation outcomes from hypotheses and theories in order to either verify or falsify such outcomes by means of measurements and tests. But it cannot be used simplistically in a manner which ignores all the relevant variables affecting each calculation. There are many variables and the world is complex. Complexity is uncomfortable for the FEer who wants reality to fit a preconceived simplistic mould, such as a highly literalist Biblical understanding of the world.
P.P.S. The black swan metaphor is related to Carl Gustav Hempel's Raven Paradox
which, imo, Oakley could have used instead to sound even more sciency. With the Raven Paradox Hempel attempts to demonstrate a type of hasty and faulty generalization perpetrated in lay reasoning:
Hempel describes the paradox in terms of the hypothesis
(1) All ravens are black
. In the form of an implication, this can be expressed as: If something is a raven, then it is black.
, this statement is equivalent
(2) If something is not black, then it is not a raven.