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  • It may seem crazy to doubt that our concept of reality is true.

  • But I think, to find the meaning of life we must answer the question:

  • is there an independent reality or not?

  • Imagine a scenario that is straight from a science fiction movie.

  • The world around you is actually nothing more than an elaborate fabrication

  • of some unknown superior intelligence.

  • A giant supercomputer provides you with all your senses

  • from what you see to what you smell, hear and touch.

  • But in fact you have no senses.

  • Your body does not exist. You are just a brain in a jar.

  • It may sound bizarre, but this is a genuine scientific hypothesis called:

  • The simulation theory.

  • For all we know, every one of our perceived reality is simply fed to us

  • by some all-powerfull supercomputer.

  • And the simulation is so perfect that we never even notice.

  • But here’s the crack: It doesn’t actually matter.

  • It’s as Descartes said: We think, therefore we are.

  • The hamburger could be nothing more than a piece of computer code.

  • But our desire to eat it, is still our own desire.

  • We still feel hunger

  • Our minds still exist, even if we are in a simulation.

  • So doubting the true nature of reality serves no purpose.

  • It’s simpler to just accept that there are fundamental limits to what we can know.

  • Take this table, for example.

  • How do you know if a table still exists if you go out of the room

  • and can no longer see it?

  • For all you know, the table could pack up and disappear out the window.

  • It could take a visit to the International Space Station.

  • Perhaps even fly to the moon.

  • All this before returning to the exact same spot and instance before you reenter the room.

  • This, of course is a pretty unlikely scenario.

  • But one we can’t rule out.

  • It is much simpler to assume that the table stays put when we are not there.

  • It is our best fit model of reality.

  • This is essentially what we do in science.

  • We create best fit models of how we believe

  • the universe actually works.

  • The ancient Greeks were the first

  • to build such scientific models.

  • They suggested that the earth was a large sphere, motionless

  • And fixed at the center of the universe.

  • But later pioneering scientist like Copernicus and Galileo

  • found a much simpler and completely revolutionary model to describe these same observations.

  • They proposed that the earth itself was spinning and orbiting the sun at the same time

  • along with all the other planets.

  • But neither can be said to actually be true.

  • Because they, like all models, are just models in our heads:

  • The best fit of reality we perceive.

  • In fact, physicists are forever creating ever more sophisticated models

  • And the truth of those models is impossible to establish.

  • A good example of this came in the 1960s.

  • When physicists devised a theory of really tiny bits of matter, called quarks.

  • These quarks were proposed to be the building blocks of the subatomic particle called:

  • A proton.

  • The theory our model suggested that

  • these quarks were held together by a force

  • that got stronger as you tried to separate them.

  • As if the quarks were bound by tiny rubber bands.

  • This model also implied that there is no way one can ever see a single isolated quark.

  • At first, some people were skeptical.

  • If something by its very definition can never be seen,

  • can it be said to exist?

  • Does it make sense to say that quarks are real or not?

  • In vast particle accelerators like this one at CERN in Switzerland

  • Scientists are on the hunt for quarks and other subatomic particles.

  • By smashing protons together at incredible speed

  • We can study the behavior of the tiniest particles in nature.

  • Although we haven’t enabled to directly observe quarks,

  • we have seen evidence of particle behavior predicted by the quark model.

  • So, do quarks exist?

  • The answer is they exist only as a model that works.

  • That is as far as we can go.

  • This is called the concept of model dependent reality.

  • And I believe that lead us directly to the meaning of life.

  • To my mind, science has taught us something pretty remarkable:

  • We humans are highly complex biological machines behaving in accordance

  • with the laws of nature. Our brains create and sustain our conscious mind

  • through and extraordinary network of interacting neurons.

  • That consciousness creates a three-dimensional model

  • of the outside world:

  • A best fit model that we call reality.

  • This reality is much more than what we see around us in our everyday life.

  • A vast array of ground and space telescopes have extended our senses.

  • Allowing us to see deep into space

  • And build a much bigger model than ever before.

  • As we peer further and further into the cosmos

  • our reality has grown bigger and bigger still

  • where once we saw a chink in heaven’s flow

  • We now see distant stars like our sun.

  • Many with their own planets and moons.

  • Then we discovered distant galaxies, home to billions more stars.

  • We have peered back in time.

  • All the way to the birth of the universe itself.

  • All this, the entire 13.7 billion year history of the universe

  • exists as a model inside our minds.

  • So, where does this leave us with finding a meaning to life?

  • The answer, I think, is pretty clear.

  • Meaning itself is simply another piece of the model of reality

  • that we each built inside our own brains.

  • Take this mother and child.

  • They each create their own little bubbles of reality in their conscious minds.

  • The youngster can create a detailed mental model

  • of his surroundings.

  • Even though he may not fully appreciate the fact he’s on the fifth floor.

  • The mother’s reality is also produced by her mind.

  • And for her, her love for her boy is as real as the telephone in her hand.

  • In short: the brain is responsible for not only the reality we perceive

  • but for our emotions and meaning too.

  • Love and honor, right and wrong

  • are part of the universe we create in our minds

  • just as a table, a planet or a galaxy.

  • It’s pretty remarkable to think that our brains

  • which are essentially a collection of particles working to the law of physics

  • have this wonderful ability to not only perceive realty

  • but to give it meaning, too.

  • The meaning of life is what you choose it to be.

  • Personally, I like to think that it is everyone of us that gives meaning to the universe.

  • We are, as cosmologist Carl Sagan once said:

  • The universe contemplating itself.

  • Meaning can only ever exist within the confines of the human mind.

  • And in this way, the meaning of life is not somewhere out there

  • but right between our ears.

  • In many ways, this makes us The Lords of Creation.

It may seem crazy to doubt that our concept of reality is true.

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Stephen Hawking's: Grand Design - The Meaning of Life / Gran Diseño - Significado de la Vida

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    Steven Hsu posted on 2016/08/08
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