1.Have you ever seen something that isn’t there? Ever heard noises that don’t exist? Did you smell that? No? My senses must be deceiving me. The ability to sense is one of the key methods of survival. The more advanced your senses are, the more chance of surviving you have in any given situation. But sometimes our senses can also be our greatest downfall, especially when they deceive us.
2. We have all had the experience of being unsure or mistaken about something: you mistake someone's voice on the phone for someone else's; you wonder whether you've locked the door after you've left the house; you think it's Tuesday when it is actually Wednesday. These sorts of situations are common and do not tend to cause most people any great deal of anxiety - we simply accept them as normal incidents. But what if we were mistaken all the time? Is this possible?
3. From the very beginnings of philosophy in ancient Greece, philosophers have been discussing this question. On one side of the discussion are the Skeptics who argue that it is impossible to be certain about anything. They point to similar examples as the ones I have given above, arguing that if we can be deceived about such simple things, who is to say that we are not mistaken more often than we think?
4. The human body has five basic senses: seeing, hearing, smelling, tasting, and touching. Everything we know about the world comes through these senses. Naturally, we trust our senses—and one sense especially, sight. More of the human brain is devoted to processing visual stimuli than to any other sense. As a result, images can carry a lot of weight in our brains—more weight even than ideas. "Seeing is believing," they say. We trust our eyes.
5. And this, unfortunately, is a fact that can be used against us. As you all know, looks can be deceiving. Advertisers can sell anyone a lemon if they package it attractively enough. Or, in another example, criminals can conceal their crimes by altering appearances. This happens all the time in detective stories. In Sir Arthur Conan Doyle’s The Hound of The Baskervilles, Charles Baskerville is found dead, and a ghostly dog with flaming jaws is seen on the moors. Many who see it believe that some demon is stalking the Baskerville family. But Sherlock Holmes is skeptical. In the end, he reveals that the hell-hound is an ordinary dog painted with phosphorus. And the real criminal is "unmasked."
6. The basic storyline of all the classic detective novels is this: looks can be deceiving, but careful observation discovers the truth! This is nothing less than the very premise of science—that a careful-enough, objective-enough, passive-enough observer will not be deceived by looks. Of course, this premise falls apart if the observer doesn’t see correctly. If a telescope is blemished, for example, it will distort everything it shows. Or, as Jesus says, "The eye is the lamp of the body…if your eyes are bad, your whole body will be filled with darkness." Sometimes when you and I are deceived by what we see, it isn’t because looks are deceiving; but because we aren’t seeing correctly. Sometimes, our own eyes deceive us.
7. Now all of you take a good look at one of your hands for a few seconds. Remember what it looks like. Done? Now stare at the center of the image on screen.
Concentrate on the image. Watch the spiraling. Isn’t it distracting? Keep watching. The point of this is to portray one of the many deceptions caused by sight. Stay concentrated on the center of the image.
8. Now when I say so, I want you all to look at the back of the hand you looked at earlier. Ready? Now look at the back of your hand. Trippy huh! Now put your hand up if you ‘saw’ your hand warping and apparently ‘boiling’. Most of you? That’s good! It should be back to normal by now. See how your eyes deceived you? What they showed you was there wasn’t actually what you can see now.
9. Another type sensory deception present in our lives are our ears. When ever you have heard something that nobody else has heard, your ears have been deceiving you. Sometimes this is in the form of the occasional strange noise that no-one else can hear, but it can also appear in the form of those friendly voices inside your head. Or am I the only one that hears them? Either way, our ears can play tricks on us! But if you hear voices too, then I reckon you should probably go get a mental sanity assessment done.
10. Many people actually ask if our senses can deceive us, Most of them think it is an opinion when it’s actually a fact; Our senses can deceive us. Even our sense of taste can deceive us! You can smell the most amazing food smell, and then go to eat that food, but it tastes like crap. And the same vice-versa, bad smelling food can end up tasting brilliant! This deception is up to your brains interpretation. When you smell something nice, naturally, you tend to go for it, rather than the bad smell round the corner even though the bad smell could be something amazing and wondrous and the good smell is a complete letdown.
11. The people that argue that our sense do not deceive us are in fact the ones being deceived by themselves. They say that it is all down to the interpretation of the information, But really, our brain decodes what it is given to decode. If your ears ‘hear’ something, then they report that to your brain, your brain processes it and then you hear it. Simple. But they argue that when we are deceived, it is because our brain isn’t given enough info about the scenario at hand. An example is this:
(find the word triangle with the sentence with a double up) (read out words in triangle) But in actual fact, there is one more word there. Your eyes didn’t see it so they weren’t able to tell your brain that it was there, meaning that your brain didn’t tell you it was there. Your eyes deceived your brain, which in turn, deceived you. But since your brain had already been deceived, it can be taken out of the equation leaving us with evidence that your senses can deceive you. The proof is crystal clear, wouldn't you agree?
12. There is, as you might guess, a great deal of debate as to whether visions - in the religious sense - actually exist. However, it is possible to classify certain experiences as delusional. For example, someone who is running a fever, has suddenly woken from a deep sleep, is exhausted through hunger or fatigue, or even under extreme stress, may hallucinate. There are also certain types of mental illness where voices are heard or things projected out onto the outside world so that they appear as real. However, the main thing to notice here is that the mind is capable of producing illusions under certain circumstances.
13. There are natural illusions in this world, these include things such as: moisture rising from the ground appearing as a pool of water (a mirage); the light of a star that has by now died but can still be seen; a stick in water that looks bent; the way the moon looks bigger nearer to the horizon.
14. These, and other examples, are often cited as proof that the senses cannot in themselves be trusted. As with the optical illusions, there seems to be a natural tendency to misinterpret, or provide misleading information regarding certain experiences.
15. Have you heard of relative or subjective sensations? As the name suggests, these subjective sensations are based only on what the subject experiences, such as how hot water to a cold hand can feel hotter than to a warm hand - and vice versa.
16. Also, people who have had a limb amputated sometimes still have sensations where the limb was. Experiences of this type suggest that even something as fundamental as our bodily sensations can be mistaken. This is an especially strong point for the skeptic because our sense of touch is very often seen as being the most reliable, the thing most capable of giving us proof. If we can touch or feel something we are more likely to accept it as real than if we have merely seen it.
17.I shall leave you today ladies and gentlemen, with one last famous quote and an explanation:
' I think, therefore I am'Possibly the best known of all philosophical quotations; from the French philosopher René Descartes. He said this attempting to prove his existence as a being, by thinking. But is that correct? Is he right in arguing that we exist just because we think? Our sense cannot show us that we exist, so is he right? I'll leave that up to you to decide.