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Is Seeing Believing?

Ratings: 7.20/10 from 5 users.


Is Seeing Believing?Horizon explores the strange and wonderful world of illusions - and reveals the tricks they play on our senses and why they fool us.

We show how easy it is to trick your sense of taste by changing the colors of food and drink, explain how what you see can change what you hear, and see just how unreliable our sense of color can be.

But all this trickery has a serious purpose. It's helping scientists to create a new understanding of how our senses work - not as individual senses, but connected together.

It holds the intriguing possibility that one sense could be mapped into another. This is what happened to Daniel Kish, who lost his sight as a child.

He is now able to create a vision of the world by clicking his tongue which allows him to echolocate like a bat.

And in a series of MRI scans, scientists are now looking to find out if Daniel's brain may have actually rewired itself enabling him to use sound to create a visual image of the world.

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32 Comments / User Reviews

  1. Wise

    Excellent doc, the part about illusions not being a weakness but an evolutionary advantage was particularly interesting :)

    definitely worth a watch!

  2. hudini

    Is it just me or is the video mirrored horizontally? I only noticed it when text appears backwards in the doc. I hope its just a bug on my end.

  3. Hesus

    Fascinating! This film goes beyond just optical illusions. One correlation between senses they did not mention is between smell and taste. Recommended!

  4. afly_on_the_wall


  5. yuneiv

    fvcking awesome. riding without eyes and finding directions without compass

  6. nomaD

    isnt it funny how scientists do all this work to come to conclusions that can be had instantly after the ingestion of sacramental entheogens like psilocybin mushrooms

  7. Arnold Vinette

    hudini - Is it just me or is the video mirrored horizontally?

    Thank was part of the optical illusion of course!

    This was a great documentary! I especially liked how our brains who be wired into a belt that senses magnetic north. I would like to try that and would find it very handy for hiking in the woods.

    I wonder how it would feel though to always know where magnetic north was.

    I thought it was cool how all of senses are intertwined and that they all work together as one and not individually.

    The beginning "da" vs "fa" experiment was so cool. I watched this several times and experimented by closing my eyes. Sure enough it was "da" all the time. But when I opened my eyes "fa" was heard. Very interesting how our brains interpret all the senses.

    I would not have believed it, if I hadn't seen it / heard it.

    Arnold Vinette
    Ottawa, Canada

  8. ponderman

    One of the best Docs Ive "tasted" on here in quite awhile. Not sure I buy the last section where they believed a new sense was forming relating to magnetic fields. I think it was just a combination of technology and touch. I think after awhile it became a finely tuned motor skill between vibrations in particular parts of the body where the belt was and the brain knowing what direction you were going, but it was the belt vibrating on the "skin" that was directing the perception.

  9. gothnate


    Sometimes, when people upload videos to YouTube and the like, they falsely think that by mirroring the video, they're circumventing any and all copyright issues.

    Good documentary though.

  10. Cool E Beans

    Video was mirrored which I thought was appropriate for the topic.

    I have always been able to locate magnetic north. I also can't wear a wind up watch. They always stop running except for the one I wore in high school which had a wide leather strap under the watch was which apparently protected it from me.

    One drawback is that sometimes I feel 'wound up' when making too many turns in one direction and then have to unwind by turning the other direction. Also when wrapping a pallet with cling film I have to go around it in a clockwise direciton. Maybe that's why I don't watch auto racing since they are always going around the track counter-clockwise.

  11. Jo McKay

    Wow wow Wonderful;imagine the possibilities - we can LEARN new senses ... lovely ... (as for the dark side possibilities, or as Jung called it, the shadow, I'll choose perceiving my reality with more hope), after all as noted here also, we decide 'in advance' what we see/hear/taste/touch - and I'm guessing smell as well. Past time me thinks to create a better reality. Cheers.

  12. Imightberiding

    Very good! Thanks for another interesting doc Vlatco.

  13. Lars

    "imagine the possibilities" Yeah, I guess we won't be having to use our cell phones any longer for navigation. It's not like I roam the wilderness and need a lot of senses. I know it sounds dull and a bit gray but what's the rush? I just see multiple ways of feeling bad during a hangover. Not only is your vision impared, your hearing super sensitive, your balance off guard, ashtray in your mouth but now you might not even stand radiation from electrical apparatues? :)

    No, really, this was a real mood lifter documentary. I'd want to get telescopic eyes so I can gaze the stars laying in the grass.

  14. Anhelo

    @hudini, I also noticed that the video is horizontally mirrored. Noticed first time when the last guy in the experiment with the belt was riding his bike around, there was a building with a banner that reads mirrored. I thought maybe they ran out of film and were just creating an illusion of a new shoot :B but credits at the end are also mirrored.

  15. demon

    Why is everything reversed ? like in a mirror, almost the whole doc long...all letters are mixed up...or is it just me ?? lolol

  16. Voice of Treason

    Letters were the right way round for me..

  17. Maxime

    ""hudini 2 Is it just me or is the video mirrored horizontally? I only noticed it when text appears backwards in the doc. I hope its just a bug on my end.""

    no Hudini its just an illusion from your brain! My brain saw the texts symetric as well... lol :P

  18. Fawzi

    They're is another upload on youtube that NOT mirrored which is also of superior quality (720P!). check BBC Horizon 2010 Is Seeing Believing ¦ 720p HD [*/4]

  19. spookz

    looks like a nice watch

  20. Chu Quan Tan

    what if the bee remembers the square with the sugar water as the one in the top left corner, not by colour?

  21. French Toasty

    This was a pretty neat doc for me. The ways in which our senses can work for us or seem to conspire against each other to fool us are quite amazing.

    The blind cyclist was awesome.

  22. diedeutsche

    This is a pretty entertaining documentary for people who want to know a bit more about perception. I also recommend it for children to widen their horizon – it is kept simple and fun to watch.

  23. EdwardNewgate

    anybody else notice on the 6th vid, at 4:51, the woman pulling down her skirt?

  24. Drake

    It's official. This is one of the most educative documentary I've seen in my life.

  25. harry nutzack

    ask any mechanic... certain complex tasks, when performed at an extreme limit of visual perception, are more easily performed with closed eyes... "braille bolt turning", for want of a better term... in my case, some fairly tactile tasks (picking a lock is a major one for me) are near impossible if visual perception is "muddying the waters", yet incredibly simple if i close eyes, or "distract" my vision with completely unrelated stimulus (a magazine, watching the activities of somebody else, etc).. very interesting and informatice doc!

  26. Nicholas Penney

    This was a great video to pass time. Nice famous faces doing interviews, a pretty good source of information.

  27. Bommer Bommer

    Awesome! Thanks!

  28. potluckpotatoes

    Only the first video in the playlist works, the rest have been removed due to copy-write infringement... I'm getting really sick and tired off this website. It use to be awesome but lately hardly any video I pick works. Would it kill them to do some house keeping and fix this sh#t or at least remove the old videos that don't work anymore? This is at least 10 videos I have tried to watch in the last 24 hours that no longer work. Get your sh#t together.

    Does anyone know if there is way to report video's no longer working? Like a simple "Report Problem" button/link?

  29. over the edge

    wow i am glad you are so grateful for all the FREE hard word the admin and moderators put in here. if you look a couple of posts down you will see that az kindly provided a alternate link. now i have an idea how about you follow her lead and when you find a video with a broken or missing link, look up an alternative yourself and provide a solution for all of us instead of a complaint. the sense of entitlement in your post is disturbing nobody here works for you and neither i or anybody else here owes you anything. now i have no affiliation with this site or those who look after it but in my personal opinion i say enjoy what if offers, try to contribute or feel free to look elsewhere for education and entertainment

  30. Achems_Razor


    There are numerous posts of you complaining about this site, vids pulled because of copy-write or not working etc: you want your money back? wait! there is no money, this site is free to you.

    As @over the edge: explained, everyone here on TDF does work hard to keep this site viable and free, no charge. This site is always striving for improvement, but sometimes things happen that are beyond our control, so instead of bitching all the time, why don't you find some alternate links as some posters do. Or, don't let the door hit you on your way out.

  31. GreatMoel

    I agree with the previous comments.

    I am grateful for this site. I think this is one of the best places on the net.
    Since I discovered it, I spend most of my spare time here browsing and learning.

    Great site, great, interesting and cultured community.

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    By the way thank you again for everybody for creating and maintaining this great place!

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