Date: Sat, 12 Jul 2008 10:19:13 -0700 (PDT)
On Jul 12, 9:33 am, Roy Hann <specia..._at_processed.almost.meat> wrote:
> Bob Badour wrote:
> > All evidence from Da Vinci until 1900 suggested birds were somehow
> > special as regards heavier than air flight.
> Ignoring bats and bumblebees, birds *were* special. They were the only
> ones that had structures that generate lift. So anyone claiming to fly
> was obliged to demonstrate they could. The same goes for anyone
> claiming to do anything else we suspect isn't possible.
There are some differences between your analogy and what I'm saying. Within the man-can-fly example, suppose it is 1880, and I'm saying "Someday it will be possible to build a heavier-than-air vehicle." Asking me to demonstrate such a vehicle fails to discriminate between solved engineering problems and theoretic possibilities. In 1900, we could look at the history of engines, and see that there was a steady increase in power-to-weight ratios, and we could look at birds, which we know to be altogether physical, nonmagical things, and notice that they possess heavier-than-air flight, and we can point to the Bernoulli principle. From there, we can easily extrapolate to say that heavier-than-air flight will happen for man someday too.
Marshall Received on Sat Jul 12 2008 - 19:19:13 CEST