In the movie "What The Bleep Do We Know" it is stated that when
Christopher Columbus first reached land, the natives could not see his
ships because the concept of the large ships did not exist to them.
Only after several days did a medicine man first see the ships and
then showed each of the other natives that they did exist. The concept
put forth is that we can only see what fits in our world view.

Question: Is there any historical reference to this fact from an
accredited source that predates 1950?

I sincerely doubt that any reputable source for the story about the
ships will be found. This sets off my BS detector. And I don't mean
"big ship."

Here you'll find a long thread discussing the matter:

http://collab.givingspace.org/forums/community/2004-08/msg00186.html

Another good discussion thread:

http://msgboard.snopes.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=36;t=000682;p=1

Oh, that must explain why I can't see the flying saucers.

I agree with Pink.  Definite BS.

Good work on that Big Ship quip too.  :)

I saw What The Bleep last autumn, and found that my rectum was rifled
with hemmoroids thereafter. That apocryphal anecdote of the natives'
inability to see & understand anything not spoon fed to them by
experts is just a tactic on the part of the filmmakers, to teach the
audience to accept their words as authorities on mystical issues. This
is, to say the least, the antithesis of healthy scientific scepticism.

-Mark

The "natives" had only oral history (nothing written), and those in
Hispaniola sadly parished quite quickly. The chances that this is
established are in my opinion slim.

This is a ridiculous idea. Columbus?s ships weren?t very big. I had a
chance to visit a replica of one of them a few years ago and it was
quite small. The native peoples of the West Indies used fairly large
dugout canoes and were quite familiar with the sea. Here are some
links that give some perspective on the scale of the ships Columbus
arrived in that supposedly so boggled the natives.

http://www.sailtexas.com/columbusships.html
Columbus Ships

http://www.kwabs.com/columbus_log.html#SHIPSANDNAVIG2
Columbus Ships and Log Book

http://www.sfu.ca/~csmith/genstuff/manteno/manteno2.html
The Manteņo Expeditions 
Investigating the Sailing Vessels of Ancient Ecuador 

http://www.webster.edu/~corbetre/haiti/history/precolumbian/tainover.htm
PRE-COLUMBIAN HISPANIOLA -- ARAWAK/TAINO NATIVE AMERICANS
The Arawak/Taino had no large animals like horses, oxen or mules to
ride or use for work. But they did have river and sea transportation.
They used dugout canoes which were cut from a single tree trunk and
used with paddles. They could take 70-80 people in a single canoe and
even used them for long travels on the sea. These dugouts allowed
fishing the few lakes of Hispaniola as well as fishing out a bit off
the coast.

I take the information given in the comments as acceptable answers to
my original question. Thank you very much.

It is true that we have no sound evidence of the fact that the natives
actualy couldn't see the ships because it cannot be confirmed. There
is no possible to find out the truth about the matter, even if there
was a historical record, it would be british history and british
perception of what happened since natives at that time did not record
historical events.
However, the point of the movie is, considering the possibility of
such an event happening. It does not matter how hard it is for us to
imagine someone not being able to see something infront of them just
because their brain had not had any background information regarding
the object. But considering the fact that its not our 'eyes' that
'see' its our brain, the hypothesis could very well be possible. Our
brain does not see 'light', our brain sees electrical impulses that
the eye sends through the optic nerve. When the brain gets the
electrical impulses, it creates an image out of them, based on the
rules that it has been pre-fed with. Rules such as 'A light with a
wavelength so and so should appear red', Hence it sees 'red'. Also
considering the fact that brain resides in a dark shell where there is
no light. Even if you close your eyes and imagine up some object, the
brain has the capability to project the object exactly how it would've
looked had it been there in reality. When you see a dream, the brain
creates an alternate reality for us based on our memories. When we
wake up, the brain is still continuing to create a reality based on
our memories and instructions. Only this time, we are not aware of
what's real, and what's imagination. Our definition of reality is
'something that everyone else can see and interact with'. But wonder,
that when we read scientific history, or go over archeological
evidence of prehistoric scientific thought, we see that in different
areas of the world, people viewed science differently. It was only
until mainstream media was introduced that every scientific ideas
started falling into place. And observations became unanimous. Maybe
it was because all humans now had the same set of rules to describe
wat they saw and percieved. Bottom line is, Science says Our brain is
mutable, and only makes sense of the information its familiar with.
Right now while you are reading this comment, your brain is also
receiving input from other places on your screen, from the books lying
next to the screen, from your girl friend shouting at you for the mess
you made in the background and a million other tiny tid-bits of
information that our brain does not focus on. So it is likely that
those native tribes, since they had no prior knowledge of a
possibility of a ship, their brains chose to ignore that tiny bit of
information just like we would 'ignore' and consider it a day dream,
if we suddenly saw snow white roller blading accross the street. Its
likely those natives also considered it a fragment of their dreams and
their brains chose to ignore it. There are alot of possibilities to
the story, but about it being as described in the movie, i doubt it.
Although the context in which it was used in the movie is very well
possible scientifically.

It seems you didn't read the previous statements. This sounds like a
plant. I'd ask Google to close this question.