Descartes' Second Rule vs. Uncertainty

In summary, Descartes' Second Rule of the Direction of the Mind states that only those objects that our mental powers seem adequate to understand should engage our attention. He believes that science, specifically Arithmetic and Geometry, provide certain and indubitable knowledge. He argues that it is better not to study at all than to occupy ourselves with difficult objects that we are unable to distinguish between true and false. He rejects the idea of embracing complete uncertainty and instead suggests trusting only what is completely known and incapable of being doubted. He concludes that in our search for truth, we should focus on objects with the same level of certainty as Arithmetic and Geometry.
  • #71
Originally posted by Lifegazer
All knowledge is derived from the reasoned analysis of sensation. Of course, it can be argued that mathematics and certain 'concepts' are derived from reason alone. But all scientific knowledge is formulated through sensation.

Nonsense. Knowledge can only be derived from actual reality, not just from reason. Reality is the arbiter on what reason is applicable and what not.

All physical-law is formulated upon, and confirmed by, sensation. Primarily the sensation of 'sight'.

Are you a physicist?

This is simply and utterly nonsense. How do you 'see' nuclear decay, alpha or gamma radiation, etc.? Physics contains plenty of phenomena that can not be perceived by the human sensory organs.
 
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  • #72
Originally posted by heusdens
Nonsense. Knowledge can only be derived from actual reality, not just from reason. Reality is the arbiter on what reason is applicable and what not.

True, but knowledge is not just a knowledge of facts. Knowledge is a collection of that which you believe, and you derive that which you believe from your "reasoned analysis of sensations", don't you?


Are you a physicist?

Calm down, count to ten, then to 100, and so on... :smile:

This is simply and utterly nonsense. How do you 'see' nuclear decay, alpha or gamma radiation, etc.? Physics contains plenty of phenomena that can not be perceived by the human sensory organs.

How did physicists happen to come to know about these things, which they cannot observe in any way?
 
  • #73
In response to all of your responses to my reponse, Yes I know and when I was younger I thought that that was the one ultimate truth that we could know with certainty. I pondered it for years but found that for me it was a dead end. I could not proceed beyond that point.
As I grew older I came to believe that thinking was being, at least being human. That they are like identities. One implies the other. I am is a given or I couldn't say or think it. A rock is but it doesn't think. To be self aware is to think. I think; therefore, "I" am.

"I know nothing." obviously can be blowing your own whistle or showing off. It can also be a sincere admission of being the opposite of a "know it all" and in possession of a seeking, inquirering mind. It's a Zen thing. :wink:
 
  • #74
Greetings !
Originally posted by Mentat
The point is that too many people think they
look smarter by doubting everything they learn.
They think that to doubt what you learn is to
have true knowledge. This is not true (according
to Descartes), and really makes you just as good
as a person who never learned it (because what
good is taking in knowledge, if you're not going
to do so with any kind of certainty? People who
have never learned that bit of knowledge also
don't have certainty on the matter, so you're
no more knowledgeable than them), and perhaps
worse, because you have given yourself the
opportunity to know more, and have not taken
advantage of it.
Thank you for the clarification Mentat, but
I understood the statement in the first place.
I simply disagree with it. It's just the
way existence/Universe works that no certainties
about it are possible. Doubt is a reasonable
necessety according to any reason, not a semantic
issue. Doubt is also important because it
teaches us respect and strangely enough often
allows us to solve problems by approaching them
from different viewpoints. (That is also
why I respect Descrates' opinion and recognize
its occasional usefullness, but I disagree with
it in general.)

Live long and prosper.
 
  • #75
Originally posted by heusdens
Let:
p : The fact that I exist
q : The fact that I think


Logical assertion:
~p -> ~q (If I don't exist, I don't think)

Which implies:
q -> p (If I think, I exist)

Fact: q
p (I think: therefore I exist)

So, Descartes first tested q, and stated affirmitive that "I think", and then concludes that "I am" (I exist).

The statement "I am, therefore I think" is not following from this, nor directly nor indirectly. While it is true that when I am not, neither I think, it is not the case that when I don't think, therefore I am not.

A stone 'IS', but it does not think. So for a stone the following is true : 'I am'. Being doesn't require thinking. Thinking on the other hand requires Being.

So, Descartes was right in that, and made the logical conclusion that from the fact that he was thinking it can be concluded that he exists/is.

This is just based on the premise that thinking requires being.
Nowhere it says however that being requires thinking. A stone is, but does not think. A river is, but does not think. The universe is, but does not think (#)


(#) although it can be argued that we are a part of the universe, and we think, it follows then also that the universe thinks...

Nope, it just follows that part of the universe thinks. The universe is a set of all things that exist, but only a minority of the things within it actually think. Therefore, if you were to take the universe as a whole, then it is an over-all non-thinking entity.
 
  • #76
Originally posted by Mentat
Well, if I may speak for lifegazer, he's shown before that that which we reason on is first "sensed/percieved" and then reasoned on. IOW, if I were to reason on why a comet's tail points away from the sun (for example), I would have to have already perceived the existence, both of the comet, and of the comet's "tail".
Well said Mentat. In fact, I have enjoyed most of your posts in this thread.
 
  • #77
Originally posted by heusdens
Nonsense. Knowledge can only be derived from actual reality, not just from reason.
What reality do you see? And what else do you see except the various co[color=sky blue]l[/color]o[color=royal blue]u[/color][color=dark red]r[/color][color=dark-blue]s[/color] (and non-colour) of light?
And what are these colours? Are they not the representations of the reality you speak of, but cannot see? Are they not the product of the sensation of sight?
This is simply and utterly nonsense. How do you 'see' nuclear decay, alpha or gamma radiation, etc.? Physics contains plenty of phenomena that can not be perceived by the human sensory organs.
Totally incorrect. Our whole theories about the atom, and of the fundamental-energy which accounts for this base building-block of existence, is derived via reasoned (mathematical) analysis of things which we can see.
Quantum-theory is derived no differently (in method) than were the classical laws of physics. Indeed; any upheld theory can only be validated by the sensation of sight - observational qualification.
I find it highly ironic that the sensation of all theories, is used as the verification of ~reality~. Very very ironic. And somewhat amusing from a philosophical point-of-view.
 
  • #78
Originally posted by Lifegazer
What reality do you see? And what else do you see except the various co[color=sky blue]l[/color]o[color=royal blue]u[/color][color=dark red]r[/color][color=dark-blue]s[/color] (and non-colour) of light?
And what are these colours? Are they not the representations of the reality you speak of, but cannot see? Are they not the product of the sensation of sight?

The reality behind the sensations, the knowledge that light is an electro-magnetic wave, and the the spectrum of light extends beyond the visible light, that is what we know by physics, and by physics only, not by our 'sensations' of reality.


Totally incorrect. Our whole theories about the atom, and of the fundamental-energy which accounts for this base building-block of existence, is derived via reasoned (mathematical) analysis of things which we can see.

When did you see an electron?

Quantum-theory is derived no differently (in method) than were the classical laws of physics. Indeed; any upheld theory can only be validated by the sensation of sight - observational qualification.
I find it highly ironic that the sensation of all theories, is used as the verification of ~reality~. Very very ironic. And somewhat amusing from a philosophical point-of-view.

Wrong again. Our sensation of sight is not the only standard. Of course our physical description should match our sensation of it.
When we see the sun goes down the horizon, we see that sun gets larger and redder. A theory of light explains the sensations we have, because of the way the light is interacting with the atmosphere, cause the red colour and the virtual increase in the sun's disk.
The reality of the electron and the atom, and quarks, can not be part of our sensation. We can only use instruments that clearify the effects of the subatomic world. And of course these instruments produce output that is meaningfull to humans. Science is performed by humans, and fits human knowledge. Would you suggest otherwise?
 
  • #79
Originally posted by heusdens
The reality behind the sensations, the knowledge that light is an electro-magnetic wave, and the the spectrum of light extends beyond the visible light, that is what we know by physics, and by physics only, not by our 'sensations' of reality.

But you can't prove this. I agree with you, please let that be known. However, I also happen to know that you cannot prove that this phenomena is actually external. It's believed by physicists, but that doesn't mean it's right.

When did you see an electron?

Ah, but did not physicists postulate the existence of an electron because of having observed what they believed to be it's effects?

Wrong again. Our sensation of sight is not the only standard. Of course our physical description should match our sensation of it.
When we see the sun goes down the horizon, we see that sun gets larger and redder. A theory of light explains the sensations we have, because of the way the light is interacting with the atmosphere, cause the red colour and the virtual increase in the sun's disk.
The reality of the electron and the atom, and quarks, can not be part of our sensation. We can only use instruments that clearify the effects of the subatomic world. And of course these instruments produce output that is meaningfull to humans. Science is performed by humans, and fits human knowledge. Would you suggest otherwise? [/B]

No, I don't think he would, but I think you've dug yourself a hole. If you say that "science is performed by humans, and fits human knowledge", then what's to prevent you from believing that human knowledge comes from the Mind of God?
 
  • #80
Originally posted by Lifegazer
Well said Mentat. In fact, I have enjoyed most of your posts in this thread.

Truth of the matter is, I don't agree with your conclusion, but I have come to realize that it is unfalsifiable (at least by empirical data, I still may be able to disprove it through rational argument (possibly not)). I defend a lot of it's premises, because a lot of it's premises are correct.
 
  • #81
Originally posted by heusdens
The reality behind the sensations, the knowledge that light is an electro-magnetic wave, and the the spectrum of light extends beyond the visible light, that is what we know by physics, and by physics only, not by our 'sensations' of reality.
The "knowledge that light is an electro-magnetic wave" is a reasoned conlusion, arrived at by applying reason to our sensations.
Reason upon sensation - this is what 'knowledge' boils down to. All scientific-knowledge is "reason upon sensation".
The reality of the electron and the atom, and quarks, can not be part of our sensation.
The knowledge of such things is gleaned via reason upon sensation, also. But I'm sure I'm correct in stating that quantum-events can be observed via effects of light. Hence, QM is a theory which is also verified through observation/sensation.
We can only use instruments that clearify the effects of the subatomic world.
"Instruments" are built by, and for, humanity. And their results are also sensed.
Science is performed by humans, and fits human knowledge. Would you suggest otherwise?
No. Although I would qualify that science is governed by a materialistic philosophy, at present. But it won't always be like this. Materialism is a philosophy which has no footings. It is an endangered species.
 
  • #82
Originally posted by Lifegazer
Materialism is a philosophy which has no footings.

This is only as true of Materialism as it is of your hypothesis, isn't it? You cannot disprove either of them.
 
  • #83
Originally posted by Mentat
This is only as true of Materialism as it is of your hypothesis, isn't it? You cannot disprove either of them.
I can promise the reader that there isn't one single rational-argument to support the basic premise(s) of materialism - that all effects have a material-cause. And then you know how I present my own argument:- with universally-experienced facts.
 
  • #84
Originally posted by Lifegazer
I can promise the reader that there isn't
one single rational-argument to support
the basic premise(s) of materialism - that
all effects have a material-cause.
That's old materialism - including the
false assumption that science reveals truth.
"New" materialism is JUST science - observation
of the Universe with no assumptions.

Live long and prosper.
 
  • #85
Originally posted by drag
That's old materialism - including the
false assumption that science reveals truth.
"New" materialism is JUST science - observation
of the Universe with no assumptions.

Live long and prosper.
*laff*
So you will no longer insist that 'thought' emanates from within the brain (matter)? And you will no longer insist that 'life' came-about via material-processes? And you will no longer insist that the BB had a material-cause?
 
  • #86
Originally posted by Lifegazer
So you will no longer insist that 'thought'
emanates from within the brain (matter)?
And you will no longer insist that 'life'
came-about via material-processes? And
you will no longer insist that the BB
had a material-cause?
I personally never did. It's just the most
probable - direct - lacking of premises
deduction from what we observe. Isn't it ? :wink:

Peace and long life.
 
  • #87
Originally posted by drag
I personally never did. It's just the most
probable - direct - lacking of premises
deduction from what we observe. Isn't it ? :wink:
Since all three of those assumptions require that you believe that all effects have a material-cause, I think that that's exactly what you support - 'materialism'.
And given my own philosophy of such matters, I'd have to say that your conclusion is utterly unfounded.
I find it laughable that you would come to the same conclusions as "old materialism", using the exact same beliefs, and have the gall to call it "new materialism."
 
  • #88
Originally posted by Lifegazer
Since all three of those assumptions
require that you believe that
all effects have a material-cause,...
And what is material-cause ? :wink:
 
  • #89
Originally posted by Mentat
But you can't prove this. I agree with you, please let that be known. However, I also happen to know that you cannot prove that this phenomena is actually external. It's believed by physicists, but that doesn't mean it's right.

Excuse me, but what are you talking here? If physicist observe physical phenomena, and use detectors that "witness" some physical phenomena regaring electrons, then what is it they are witnessing?

Do you claim that all the physicists did was looking at their own navel or something? What do you mean with "external"? External to what? The mind? The mind does not exist in forms of electrons (the brain of course consists of things like electrons, but that is something different), so they can't be witnessing an "internal" electron.

You are only right that all we can say and know about the "electron" being really out there that it has some properties according to some model of the electron, that makes it possible for us to calculate things and predict the behaviour of electrons.
That is of course a necessary property the model of the electron should obey, else it would be a false theoretical model, if the electron would not behave predictably.

Ah, but did not physicists postulate the existence of an electron because of having observed what they believed to be it's effects?

Yes, they did observe the electron. But to see an electron, with the human eye is not what is being stated there. Science can and does observe things that are unobservable for the human perceptory organs.


No, I don't think he would, but I think you've dug yourself a hole. If you say that "science is performed by humans, and fits human knowledge", then what's to prevent you from believing that human knowledge comes from the Mind of God?

Nothing. But then this 'Mind of God' must be put in the form of a scientific hypothese, and must be explorable. If the hypothese is to be stated true, then there must be some objective scientific evidence for it that can either state the 'Mind of God' does exist, or does not exist.

So far I have not seen any workable scientific hypothese about the existence of the 'Mind of God'.
 
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  • #90
Originally posted by heusdens
So far I have not seen any workable scientific hypothese about the existence of the 'Mind of God'.
You should do some serious reading about the placebo-effect... and the power of thought (positive & negative).
 
  • #91
Originally posted by Mentat
True, but knowledge is not just a knowledge of facts. Knowledge is a collection of that which you believe, and you derive that which you believe from your "reasoned analysis of sensations", don't you?

That I don't disagree with, but when you leave out the observation of reality and with that I mean a structured and scientific exploration of the phenomena of reality, you would then suggest that to come up with a viable theory of reality, you could sit at your desk, and just think and reason, and then all of a sudden can "create" a viable theory on reality.

Which is not how it goes, of course.


How did physicists happen to come to know about these things, which they cannot observe in any way?

They did that because to explain the phenomena we CAN observe (for example sound and light) we wanted to have a scientific explenation of these pehenomena. And we came up with a theory of light for example as a wave phenomena. A wave has properties of Energy, frequency and wavelengt, which interrelate in an orderly way.

E = hf (energy = Planck constant times frequency)

Since the variable in this formula is the frequency, it was then assumed that light also exists beyond the frequencies of visable light.
In fact, other forms of light were already known, but they were seen as different phenomena as visible light. For example heat radiation, we can sense, but we can not see infrared light.
The theory of light explained what the connection was between these various phenomena.
 
  • #92
Greetings !
Originally posted by drag
And what is material-cause ? :wink:
Let me help you out here LG. :wink:
What you call material-cause (don'no why) is
what we observe. :wink:
So who's view biased ?
Of the person who only reasons with what is
observed or of the person who, in addition,
assumes that our mind creates what is observed
and all the various additional assumptions
that are connected to this enitial unprovable
assumption ? :wink:

Peace and long life.
 
  • #93
Originally posted by heusdens
They did that because to explain the phenomena
we CAN observe (for example sound and light)
we wanted to have a scientific explenation
of these pehenomena. And we came up with a
theory of light for example as a wave
phenomena. A wave has properties of Energy,
frequency and wavelengt, which interrelate
in an orderly way.

E = hf (energy = Planck constant times frequency)

Since the variable in this formula is the
frequency, it was then assumed that
light also exists beyond the frequencies
of visable light.

In fact, other forms of light were already
known, but they were seen as different
phenomena as visible light. For example
heat radiation, we can sense, but we
can not see infrared light.
The theory of light explained what the
connection was between these various phenomena.
So, basicly what science does is to try to assume
the most direct connection that is possible.
Minimum relations and minimum entities.

Live long and prosper.
 
  • #94
Originally posted by drag
So, basicly what science does is to try to assume
the most direct connection that is possible.
Minimum relations and minimum entities.


If you mean that a scientific explenation, which could in principle be based on the existence of a Giant Big Applepie that exists outside time and space, and connects in a spiritial way to everything there is and can explain everything there is, to explain for instance gravity, and we have an alternative theory, that explain gravity based on interaction between massive matter on a distance, it is indeed true that the Giant Big Applepie, will be eliminated from scientific reason, and we will adopt the more simple and provable option, indeed.
 

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