Reason and Experience- What do we actually know for certain?

[EV]

I've been revising for my upcoming Philosophy exam again. Just been looking into the wonders of Descartes, and his 'Cogito Ergo Sum'. I thought I'd share this with you, because it is fairly interesting!

For those who don't know of it, Descartes basically visualised a table with everything on it, and took everything off that he could not be certain existed.

If you present the brain in a vat argument (that we may just be having our entire existence fed into a brain in a laboratory with the input controlled by a computer), which is now more likely known as the 'Matrix Argument', there is no way that we can know for certain what actually exists and what does not.

Descartes got a massive headache, and eventually realised that the only thing that he was sure about was that he existed, because he must exist to ask the question of whether he exists before.

There is obviously considerable debate on whether we know all of this for certain, because it depends on whether you think that you have innate knowledge or not. If all of our experience comes from experience, and the only way we can experience the world is through our senses, then our entire perception of the world is fallible and could be false. If you approach from a rationalist viewpoint, then you can use reason to experience the world. However, how do you learn advanced reasoning except through experience?

Descartes was an avid Christian, and unfortunately decided to try and use the fact that we could not be sure that anything existed as an argument for the existence of God. He basically summarised his argument like this:

1. I have an idea of supremely perfect being, i.e. a being having all perfections.
2. Necessary existence is a perfection.
3. Therefore, a supremely perfect being exists.

He used the fact that there is nothing we know for certain, and used the fact that some ideas are innate to formulate this. Of course it is a load of bullshit. We can show that we got the idea of a supremely perfect being through experience, which is fallible. And if the idea is fallible, according to Descartes's own logic, it actually fails through his own argument!

Anyway, this is some revision of my Reason and Experience module, I just thought it was fairly interesting, and wanted to share with you guys. Would like to see what our resident (like 3) Christians make of this refutation of the Ontological argument.

-ElliotViola

[One Above All]

The answer depends on how you define "for certain". If you mean proof like how you can prove that 1+1=2, then we know nothing. Anything we think we know is due to experience. Since we can't prove that our experience is real, we can't know anything.

[Historicity]

I've read a little more Descartes than you have so I'll give you his answer.[1]

"You have to be crazy to think that the world doesn't exist."   That's a slight paraphrase but he did say "crazy".

In other words he recognized he had painted himself into a corner.

A young Earth creationist (bear with me) at Quodlibeta had this paradoxical observation about "brain in vat":
http://bedejournal.blogspot.com/2012/03/skepticism-and-agrippas-trilemma.html

... that for all we know we may be, e.g., brains in vats being stimulated to think there is an external world. ...  Any evidence we could have, any test we could construct to make sure that the world we experience really exists, is just as readily explained by the skeptical theory. ... Hilary Putnam has argued, brilliantly, that on a linguistic-externalist view our words obtain their meaning by virtue of their relation to their object in the world. So our word "vat" means something because there are vats in the external world. But then in order for the brains-in-vats skeptical scenario to be correct, it has to be based on an actually experienced external world, which of course contradicts the scenario.

Not all that "brilliantly".  A.J. Ayer addressed that in Language, Truth and Logic in 1936 with his term "the sense contents" of a word.

He has a straw man there.  Of course "brain in vat" is a tag for a more general situation.  It could be be a program in a computer being fed data files.  I only recently heard "brain in vat" bandied about tho I've seen Donovan's Brain a couple times.  I never even assumed a computer.  I always imagined myself as a bodiless "it" suspended in darkness.

Having imagined myself alone, I had to wonder if I have created this world from my imagination.  Shakespeare wondered that in Midsummer Night's Dream.  Rod Serling had a Twilight Zone episode with a man picking up a woman in a trench coat hitchhiking in the rain who go to a diner and something happens...  And then again and again.  In one scenario as the man is dying of a bullet wound he says he knows they are being created and manipulated by a God and He hasn't gotten it right yet.  Then it cuts to a writer ripping a page out of a typewriter and complaining to his wife that he has a writer's block.

And that solved it for me.  A great writer like Shakespeare or Serling could wonder.  I, on the other hand, know I do not have enough imagination to create the world I experience.

So I have to postulate at least one other source pouring the information in.  There has to be one other person.  And if there is more than one there could be others.

So I am saved from that by my second rate mind.

1.	It was in one of those excerpts from great philosopher books.

[ParkingPlaces]

The problem with knowing things for "certain" is that the only standard we hold for such a concept is the one in our head that tells us when we are certain. We use a non-feedback loop thinking it is giving us good information, when it fact almost everything we know is an assumption rather than a fact.

I know for certain what it takes to stub a toe and how it feels. Most everything else is made up in my head, but I don't know it. I can muse over the possibility, but I can't convince myself that I am that wrong about the world. Like others, I smart enough to lie to myself about my own righteousness, which, for the sake of convenience, I have labeled "rationality".

I don't know a damned thing about how little I know, but at least I know how little everyone else knows. You poor suckers. 

[Poseidon]

A succint summary might lie within that familiar uttering; "We don't know what we don't know".

Historicity, you are conspicuously overmodest with that second rate mind bit.

[dloubet]

We may not know if the world we perceive is real, but we can measure the consistency of that world and thus claim knowledge about it.

The reality of the world we perceive is irrelevant if it's the only world we can perceive. Treating it as real is the only option because our well being depends on it.

[Add Homonym]

So I am saved from that by my second rate mind.

Er, how do you know you are dumb? You could be composed of a primary mind, which is quite inventive - which say, leaks through in your dreams and inspiration, and the there is a restriction in your conscious thought, that makes you think you are dumb. Another way of looking at it, is that what you think you know, may be a load of balderdash - like when you wake up from a dream, and you think you just dreamed something awesome, but it was actually complete rubbish. I may think evolution and QM are awesome now, but when I wake up, they may seem like total rubbish.

[jeremy0]

Einstein quotes of the day -
"Reality is merely an illusion, albeit a very persistent one."  To understand your (any of you) realities is incomprehensible to me, since we haven't had the same 'experiences'.  Also, the chemical compounds and existence that we know in this universe, may be different in some other universe, according to speculative theory..  (see M-Theory, uh, quarks might get you started down the same path.. wikipedia)
"Anyone who has never made a mistake has never tried anything new." - you can tell by some of my, er, irrational statements in past posts..
"Great spirits have often encountered violent opposition from weak minds." - see rockV12..
"Common sense is the collection of prejudices acquired by age eighteen." - again, experiences you come to know as you age.
"We can't solve problems by using the same kind of thinking we used when we created them." - an earlier post I had on politics, applies to this - to think you don't know something when you've studied it, it's safe to say you know it to be real.  Reality is simply what we can perceive, and nothing more.  What's not reality are things that you have dreamed up, but never actually happen or has happened in observable or unobservable timescales..
"As far as the laws of mathematics refer to reality, they are not certain, as far as they are certain, they do not refer to reality." - He states over and over that reality is based on our own observation.  The observer being many different things - all observing the same thing, but agreeing on something different about that observation.  Our observations are based on our own experiences, dna, and prejudices.  That's why we can't fully agree on reality.  However, there are things that every human being *ought* to agree on every observation, and that is undeniable facts and clear reasoning.  The mathematical equasion for every observer agreeing on an observation is clearly defined in a post I had with a particle physics person, which was necessary for me to know...

[gonegolfing]

Are we certain that it is correct to be atheists ?

If so, how ?

If not, then why are we ?

 

[velkyn]

I'm quite certain that a lot of reality is very universal and objective.  if you don't think so, then stick your hand in a pour of white hot iron. 

[stuffin]

What's the line in that song?

"People say believe half of what you see
Son, and none of what you hear"
 
(Norman Whitfield and Barrett Strong)

That may or may not be real, but it is true.

[EV]

Are we certain that it is correct to be atheists ?

If so, how ?

If not, then why are we ?

 

If we exist, it is logically most sensible. If we don't exist, then I am not quite sure what to say.

I'm quite certain that a lot of reality is very universal and objective.  if you don't think so, then stick your hand in a pour of white hot iron. 

Ahh, but I may not be real to feel the pain

Am I real?

[Truth OT]

Certainty doesn't seem to be a concept that we can know as even being possible. With that in mind, I'll settle for being able to be sure beyond a REASONABLE doubt. It ain't certain, but it is a good bases for inference.

[magicmiles]

Being Australian helps you a lot with this sort of thing. I can know for certain that the weather will be fantastic sometime in the next few days, that I will see some really hot girls at the beach and that Americans talk funny.

[jeremy0]

Am I real?

Only on agreeable observations.  My observation is that because you can make statements so fantastically, and I haven't came up with a computer algorithm to make you into AI yet, then by all my observations you are, in fact, real.  Also, since most humans have made the observations that hot things burn, and therefore hurt  you, almost every human would agree on that observation and therefore not want to stick their hands in molten iron..   

[velkyn]

Ahh, but I may not be real to feel the pain

Am I real?

I'm pretty sure you think you are since you seem to be refusing to take my challenge. 

[RNS]

The whole brain in the vat thing reminds me of John Locke's veil of perception.
Some interesting things to be read on related topic here: http://en.wikipedia.org/wiki/Direct_realism

I would revise Descartes' famous saying to "existence exists" for complete accuracy. After that I don't think anything can be know with 100% certainty. I'm not sure how important it is either. Haven't ever gone back to these subjects since I got into 5-7 years ago.. actually around when I first joined the forum I think!

A more important topic would be on how to judge what to assume as true rather that what definitely is. So epistemology.
i.e. maybe I'm real or maybe I'm in the matrix. Either way I'm stuck here so I'll take it as it is and trust my senses and see what I can do from there!
I mean Descartes and all that is a nice place to start if you're just getting into philosophy, but I wouldn't get my knickers in a twist about it.

UNLESSS... you figure it out that none of this is real and unlock the next level of conciousness ..and then the next and the next and the next until your creator (which could be yourself) reveals themselves![1] Basically like everything else in life, there is a 50/50 chance that we have imagined our own lives. Either we have or we haven't: 50/50!

1.	boss level