Letter from Leibniz

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Reply Wed 5 Dec, 2007 12:11 pm
In this letter from G. W. Leibniz (1646-1717) he talks about how reason is within us a priori. This seems a fine exposition of philosophical rationalism.


...BEING ITSELF AND TRUTH ARE NOT known wholly through the senses; for it would not be impossible for a creature to have long and orderly dreams, resembling our life, of a sort that everything which it thought it perceived through the senses would be but mere appearances. There must therefore be something beyond the senses, which distinguishes the true from the apparent. But the truth of the demonstrative sciences is exempt from these doubts, and must even serve for judging of the truth of sensible things. For as able philosophers, ancient and modern, have already well remarked: -if all that I should think that I see should be but a dream, it would always be true that I who think while dreaming, would be something, and would actually think in many ways, for which there must always be some reason.

Thus what the ancient Platonists have observed is very true, and is very worthy of being considered, that the existence of intelligible things and particularly of the Ego which thinks and which is called spirit or soul, is incomparably more sure than the existence of sensible things; and that thus it would not be impossible, speaking with metaphysical rigor, that there should be at botton only these intelligible substances, and that sensible things should be but appearances. While on the other hand our lack of attention makes us take sensible things for the only true things. It is well also to observe that if I should discover any demonstrative truth, mathematical or other, while dreaming (as might in fact be), it would be just as certain as if I had been awake. This shows us how intelligible truth is independent of the truth or of the existence outside of us of sensible and material things.

This conception of being and of truth is found therefore in the Ego and in the understanding, rather than in the external senses and in the perception of external objects.

There we find also what it is to affirm, to deny, to doubt, to will, to act. But above all we find there the force of the consequences of reasoning, which are a part of what is called the natural light. For example, from this premise, that no wise man is wicked, we may, by reversing the terms, draw this conclusion, that no wicked man is wise. Whereas from this sentence, that every wise man is praiseworthy, we cannot conclude by converting it, that everyone praiseworthy is wise but only that some praiseworthy ones are wise. Although we may always convert particular affirmative propositions, for example, if some wise man is rich it must also be that some rich men are wise, this cannot be done in particular negatives. For example, we may say that there are charitible persons who are not just, which happens when charity is not sufficiently regulated; but we cannot infer from this that there are just persons who are not charitible; for in justice are included at the same time charity and the rule of reason.

It is also by this natural light that the axioms of mathematics are recognized; for example, that if from two equal things the same quantity be taken away the things which remain are equal; likewise that if in a balance everything is equal on the one side and on the other, neither will incline, a thing which we foresee without ever having experienced it. It is upon such foundations that we construct arithmetic, geometry, mechanics and the other demonstrative sciences; in which, in truth, the senses are very necessary, in order to have certain ideas of sensible things, and experiments are necessary to establish certain facts, and even useful to verify reasonings as by a kind of proof. But the force of the demonstrations depends upon intelligible notions and truths, which alone are capable of making us discern what is necessary, and which, in the conjectural sciences, are even capable of determining demonstratively the degree of probability upon certain given suppositions, in order that we may choose rationally among opposite appearances, the one which is greatest. Nevertheless this part of the art of reasoning has not yet been cultivated as much as it ought to be.

But to return to necessary truths, it is generally true that we know them only by this natural light, and not at all by the experiences of the senses. For the senses can very well make known what ought to be or could not be otherwise.

For example, although we may have experiences numberless times that every massive body tends toward the centre of the earth and is not sustained in the air, we are not sure that this is necessary as long as we do not understand the reason of it. Thus we could not be sure that the same thing would occur in air at a higher altitude, at a hundred or more leagues above us; and there are philosophers who imagine that the earth is a magnet, and as the ordinary magnet does not attract the needle when a little removed from it, they think that the attractive force of the earth does not extend very far either. I do not say that they are right, but I do say that one cannot go very certainly beyond the experiences one has had, when one is not aided by reason.

This is why the geometricians have always considered that what is only proved by induction of by examples, in geometry of in arithmetic, is never perfectly proved. For example, experience teaches us that odd numbers continuously added together produce the square numbers, that is to say, those which come from multiplying a number by itself. Thus 1 and 3 make 4, that is to say 2 times 2. And 1 and 3 and 5 make 9, that is to say 3 times 3. And 1 and 3 and 5 and 7 make 16, that is 4 times 4. And 1 and 3 and 5 and 7 and 9 make 25, that is 5 times 5. And so on.

1+3=4, 2*2=4.

1+3+5=9, 3*3=9.

1+3+5+7=16, 4*4=16

1+3+5+7+9=25, 5*5=25

However, if one should experience it a hundred thousand times, continuing the calculation very far, he may reasonably think that this will always follow; but he does not therefore have absolute certainty of it, unless he learns the demonstrative reason which the mathematicians found out long ago...

...IN truth there are experiments which succeed numberless times and ordinarily, and yet it is found in some extraordinary cases that there are instances where the experiment does not succeed. For example, if we should have found a hundred thousand times that iron put all alone on the surface of water goes to the bottom, we are not sure that this must always happen. And without recurring to the miracle of the prophet Elisha, who made iron float, we know that an iron pot may be made so hollow that it floats, and that it can even carry besides a considerable weight, as do boats of copper or of tin. And even the abstract sciences like geometry furnish cases in which what ordinarily occurs occurs no longer. For example, we ordinarily find that two lines which continually approach each other finally meet, and many people will almost swear that this could never be otherwise. And nevertheless geometry furnishes us with extraordinary lines, which are for this reason called asymptotes, which prolonged ad infinitum continually approach each other, and nevertheless never meet.

This consideration shows also that there is a light born within us. For since the senses and inductions could never teach us truths which are thoroughly universal, nor that which is absolutely necessary, but only that which is, and that which is found in particular examples; and since we nevertheless know necessary and universal truths of the sciences, a privilege which we have above the brutes; it follows that we have derived these truths in part from what is within us. Thus we may lead a child to these by simple interrogations, after the manner of Socrates, without telling him anything and without making him experiment at all upon the truth of what is asked him. And this could very easily be practised in numbers and other similar matters.

I agree, nevertheless, that in the present state the external senses are necessary to us for thinking, and that, if we had none, we could not think. But that which is necessary for something does not for all that constitute its essence. Air is necessary for life, but our life is something else than air. The senses furnish us the matter for reasoning, and we never have thoughts so abstract that something from the senses is not mingled therewith; but reasoning requires something else in addition to what is perceivable by the senses...


[A letter by Leibniz to Queen Sophie Charlotte of Prusia in 1702]
 
Arjen
 
Reply Wed 5 Dec, 2007 01:24 pm
@Pythagorean,
Nice post Pythagorean. May I ask why Leibniz wrote the letter and what your intent is with posting the letter?
 
Pythagorean
 
Reply Wed 5 Dec, 2007 02:08 pm
@Arjen,
Arjen wrote:
Nice post Pythagorean. May I ask why Leibniz wrote the letter and what your intent is with posting the letter?


Thank you, Arjen.Smile I posted this letter because I just think that certain people are maybe glib and a bit hasty when they say (as they do) that knowledge comes through external sense experience alone. This letter should here provide some substance to the 'rationalist' counter-argument, which is, that appearances are not all that there is and that we know what we know due, at least in part, to reasoning about the nature of things. So it's also, in a sense, a defense of philosophy in the classical dispensation as speculative or 'disinterested' contemplation.

As far as the motives for Leibniz's writing the letter to Queen Sophie Charlotte, it's a good question but I just don't have that information on hand at the moment, sorry to say.
 
NeitherExtreme
 
Reply Wed 5 Dec, 2007 02:19 pm
@Pythagorean,
Pythagorean wrote:
I agree, nevertheless, that in the present state the external senses are necessary to us for thinking, and that, if we had none, we could not think. But that which is necessary for something does not for all that constitute its essence. Air is necessary for life, but our life is something else than air. The senses furnish us the matter for reasoning, and we never have thoughts so abstract that something from the senses is not mingled therewith; but reasoning requires something else in addition to what is perceivable by the senses...

Wow, I really like this final paragraph. I had come to the same conclusion as the first sentence on my own when I first thought about A Priori, etc. But I had never finished it up with the rest of his thinking, which I believe completes the picture to some extent. Once again in a classic debate of X vs. Y, the truth is neither and both... Smile
 
kennethamy
 
Reply Wed 5 Dec, 2007 08:25 pm
@NeitherExtreme,
NeitherExtreme wrote:
Wow, I really like this final paragraph. I had come to the same conclusion as the first sentence on my own when I first thought about A Priori, etc. But I had never finished it up with the rest of his thinking, which I believe completes the picture to some extent. Once again in a classic debate of X vs. Y, the truth is neither and both... Smile


No one, I think, really believes that the senses alone can provide us with knowledge. But the question then becomes what is the place of the a priori in the acquisition of knowledge. Empiricists hold that reasoning allows us to move from the senses to knowledge, but the a priori cannot, alone provide us with knowledge. Leibniz, along with the other Rationalists, held that we can have a priori knowledge, and that reason alone can tell us about the world. This is a fundamental difference about the role of the a priori.
 
Fido
 
Reply Thu 6 Dec, 2007 09:38 pm
@Pythagorean,
Pythagorean wrote:
In this letter from G. W. Leibniz (1646-1717) he talks about how reason is within us a priori. This seems a fine exposition of philosophical rationalism.


...BEING ITSELF AND TRUTH ARE NOT known wholly through the senses;


I would deny this because it is through the senses that we grasp reality, and reality which teaches us reason. He agrees with this in pointing to a balance scale from which two equals are removed from either side. In that case reason must equal gravity in the conlusions it reaches. Yet, it is through the mind that we know meaning. However impossible it is to judge anything in existence of all that makes up its being, we still abstract a sense of meaning from all being.

Quote:


for it would not be impossible for a creature to have long and orderly dreams, resembling our life, of a sort that everything which it thought it perceived through the senses would be but mere appearances. There must therefore be something beyond the senses, which distinguishes the true from the apparent. But the truth of the demonstrative sciences is exempt from these doubts, and must even serve for judging of the truth of sensible things. For as able philosophers, ancient and modern, have already well remarked: -if all that I should think that I see should be but a dream, it would always be true that I who think while dreaming, would be something, and would actually think in many ways, for which there must always be some reason.

Again reason follows reality.
Quote:


Thus what the ancient Platonists have observed is very true, and is very worthy of being considered, that the existence of intelligible things and particularly of the Ego which thinks and which is called spirit or soul, is incomparably more sure than the existence of sensible things;

More sure, and the meaning of this is the same for every person. We are most sure of our own lives, to which every other life and form of being is secondary. We sense first ourselves and then sense reality.
Quote:



and that thus it would not be impossible, speaking with metaphysical rigor, that there should be at botton only these intelligible substances, and that sensible things should be but appearances. While on the other hand our lack of attention makes us take sensible things for the only true things.


This is true in the sense that while we are to ourselves the only true thing it is seldom the point of any controversy. There are only two things to people: ourselves and reality. It does not matter that our selves are part of some one elses reality because they are part of ours. Yet we externalize all of reality. No one goes about saying I am real and you are not. We take our reality for granted to the extent that we usually do not question it. Yet we say the meaning of life, or the meaning of this or that. If we are all we know as real, and our lives are our sole means of experiencing reality, then, life is the sole source of meaning. Life is meaning. All things external to life mean in relation to our lives. It is wrong to believe things mean on their own. They may exist on their own, but we give them meaning as they demand it in importance to our lives.
Quote:

It is well also to observe that if I should discover any demonstrative truth, mathematical or other, while dreaming (as might in fact be), it would be just as certain as if I had been awake. This shows us how intelligible truth is independent of the truth or of the existence outside of us of sensible and material things.

I take this in support of what I said above, that truth as perceive is a part of reality in our thoughts; but in the reality of our lives, truth is a kind of meaning that we give to what we percieve in reality. The question should be asked always: Who is truth true to? Is that a tongue twister?
Quote:

This conception of being and of truth is found therefore in the Ego and in the understanding, rather than in the external senses and in the perception of external objects.

Being and truth are not in reality, but in our minds, again as a meaning, a judgement, or a value. What is real is real without us, but reality is meaningless without us.
Quote:

There we find also what it is to affirm, to deny, to doubt, to will, to act. But above all we find there the force of the consequences of reasoning, which are a part of what is called the natural light.[A letter by Leibniz to Queen Sophie Charlotte of Prusia in 1702]


A judgement of consequences is a meaning we attach to all things in reality. If they have no consequences they will have less meaning.
Thanks
 
Arjen
 
Reply Fri 7 Dec, 2007 04:58 am
@Fido,
Quote:

As far as the motives for Leibniz's writing the letter to Queen Sophie Charlotte, it's a good question but I just don't have that information on hand at the moment, sorry to say.

That, indeed, is a shame.

Replying to Pythagorean, NeitherExtreme, kennethamy and Fido:
When speaking of how information presents itself to us we cannot ignore the senses, nor the cognitive faculties. Both have a prt to play. David Hume, in his work "An Enquiry into Human Understanding", supports the opinion that if ever we have an a priori judgement on anything, it is made on the basis of a posteriori judgements of prior experiences or perceptions. He bases his thoughts on the fact that if we mean to structure things, we need prior information to compare our perceptions to.

Hume's work awoke Immanuel Kant from his dogmatic slumber, as he calls it himself. Kant concluded that what David Hume was speaking of is called metaphysics, on account of the judgements being made being synthesised and a priori. Kant goes on with his reasoning stating that if indeed we need some form of knowledge to structure our perceptions, then it would be necessary to have a pure a priori conception to structure our first perceptions or our perceptions would never result in thought objects, nor in thoughts.

These pure a priori conceptions he calls transcendental. According to Kant these transcendental a priori conceptions are necessary conditions for reasoning and for perceiving. In that sense neither perception, nor reason are the primary way information is "fed" to us. Our a priori conceptions are. That is also why neither and both of the rationalist and empiricist opinions are true at the same time. There is an ontological difference between the transcendental and the empiric/rational truth.

When one states either the empirical or the rational comes first, one uses an incorrect syllogism, which borders on paradoxal. The things we percieve and think of are in a sense, quantifications from the conditions of their existance.

I hope this is in any way clear to someone..Wink
 
Pythagorean
 
Reply Fri 7 Dec, 2007 05:21 am
@Fido,
In light of Leibniz's claims, I would like to know if anybody here thinks it is indeed possible that we are at all being deceived in our ordinary life in what we normally take to be reality? I mean, is everything that we 'experience' day to day just what it appears to be upon the surface? Isn't there at times a demand of effort made upon us to try and figure out what is really taking place at a certain time? Don't we have to inquire after a higher or more fundamental set of rules in order to seperate things true from things that are not apparent?

I mean, what is the use of philosophy if we believe that there's nothing under the surface that could furnish us with a brighter conception of their nature? And what is the purpose of science besides its practical benefits of improving health etc? Aren't we looking for the truth here?

If we are looking for truth, then the question arises as to how do we go about in the search; -?

Are we dreaming? It seems an important and perfectly reasonable question for someone to ask. And it seems to me that the way in which we attempt to answer this question is what makes us more or less 'empiricists' or more or less 'rationalist' philosophers.

The foundations of the Universe seem to be rational and they correspond to the reasonable, thinking person's mind. That is, I say, we are at one with the universe when we use our reason to formulate the laws of nature.

----------

[CENTER]"The human intellect understands some propositions, namely those of the mathematical sciences, quite perfectly, and in these it has as much absolute certainty as Nature herself. Of course the Divine intellect knows infinitely more propositions than we do, since it knows all. Yet in respect of those few which the human intellect does understand, I believe its knowledge equals the Divine in objective certainty--for here it succeeds in understanding necessity, than which there can be no greater certainty (Galileo Galilei, Dialogo sopra i due massimi sistemi del mondo, Ptolemaico e Copernicano, 1632). [/CENTER]
 
Fido
 
Reply Fri 7 Dec, 2007 06:42 am
@Pythagorean,
Pythagorean wrote:
In light of Leibniz's claims, I would like to know if anybody here thinks it is indeed possible that we are at all being deceived in our ordinary life in what we normally take to be reality? I mean, is everything that we 'experience' day to day just what it appears to be upon the surface? Isn't there at times a demand of effort made upon us to try and figure out what is really taking place at a certain time? Don't we have to inquire after a higher or more fundamental set of rules in order to seperate things true from things that are not apparent?


Everything is for the most part what it seems to be on the surface. We can remove layers of reality from every single thing only to find another under. I am not saying it is not entertaining. It is the one fact of life that actually makes me believe there is a God. Yet, the essential question is not essence, but meaning. We can see what it is, and looking harder and deeper does not reveal more per unit of effort; but, to find meaning requires a relation of self to the being. Who does it mean to?

Quote:


I mean, what is the use of philosophy if we believe that there's nothing under the surface that could furnish us with a brighter conception of their nature? And what is the purpose of science besides its practical benefits of improving health etc? Aren't we looking for the truth here?

If we are looking for truth, then the question arises as to how do we go about in the search; -?


The same question one may ask of reality can be asked of philosophy or science; and that is: What is the use? Use is a form of meaning, just as is truth. You will hardly discover something untrue in finding a use. But use is a form of meaning that contributes to reaching the goal of all human activity: The Good.
Quote:

Are we dreaming? It seems an important and perfectly reasonable question for someone to ask. And it seems to me that the way in which we attempt to answer this question is what makes us more or less 'empiricists' or more or less 'rationalist' philosophers.

The foundations of the Universe seem to be rational and they correspond to the reasonable, thinking person's mind. That is, I say, we are at one with the universe when we use our reason to formulate the laws of nature.

If the goal of truth is yours, does it matter how you get there? What is true has to be true in relation to some one, in this case, you. Were you not always true? Did your genes not have to tell the truth, and all your people from beyond time have to be true, that is, real, for you to be real? And does the truth you discover not have to be true to future generations to be truly true today? Truth is a meaning, and what it means is survival, or a better survival for all. If my truth means your death it has failed one of us. So, when people look for A'priori truth with which to compare the truth of the world around them, it is found in the self.

It seems to me that you are putting your horse before your cart just as the medieval philosophers did. They looked at nature, -saw it behaved in an orderly fashion and surmised this as proof of a rational God. You say the same in -the foundations seem rational above. Let me suggest that it is what it is, and we are rational in relation to it. What does ratio (rational) mean? It is the balance scale leibniz was referring to applied to all reality. And what does reasonable mean? I think it comes from Latin Res, which means thing. Reason and rational follow reality. If reality were in every sense totally different, then it would change our whole grasp of reasonable and rational, -if, we had become real ourselves. In looking at nature like the ocean through a porthole we lose sight of the fact that we follow the same laws as it.

Quote:

----------


[CENTER]"The human intellect understands some propositions, namely those of the mathematical sciences, quite perfectly, and in these it has as much absolute certainty as Nature herself. Of course the Divine intellect knows infinitely more propositions than we do, since it knows all. Yet in respect of those few which the human intellect does understand, I believe its knowledge equals the Divine in objective certainty--for here it succeeds in understanding necessity, than which there can be no greater certainty (Galileo Galilei, Dialogo sopra i due massimi sistemi del mondo, Ptolemaico e Copernicano, 1632). [/CENTER]

Galileo was wrong and the Pope was right in at least one regard. If you accept the ultimate power of God, then God can do as God pleases without regard to human laws like necessity. I trust that Galileo was talking of necessity as cause and effect, that every effect, of necessity, has a cause, and every cause an effect. Certainly, not every potential cause has an effect even if every effect has a cause. We do not have cause and effect as an a'priori. We do learn at a very early age that if hungry and then fed, that hunger fled. Other than that, certainty has great meaning for some, but absolute certainty is illusion.
 
kennethamy
 
Reply Fri 7 Dec, 2007 09:54 am
@Fido,
Fido wrote:
I would deny this because it is through the senses that we grasp reality, and reality which teaches us reason.



How, would you say, do we know that all dogs are animals, or that all bachelors are unmarried males? Or, that things equal to a third thing, are equal to each other? Or, even, that if I know that X is y, then I know that X is y is true? What did I sense, to know any of these?
 
Pythagorean
 
Reply Fri 7 Dec, 2007 11:08 am
@Fido,
Fido wrote:


Everything is for the most part what it seems to be on the surface. We can remove layers of reality from every single thing only to find another under. I am not saying it is not entertaining. It is the one fact of life that actually makes me believe there is a God. Yet, the essential question is not essence, but meaning. We can see what it is, and looking harder and deeper does not reveal more per unit of effort; but, to find meaning requires a relation of self to the being. Who does it mean to?



The same question one may ask of reality can be asked of philosophy or science; and that is: What is the use? Use is a form of meaning, just as is truth. You will hardly discover something untrue in finding a use. But use is a form of meaning that contributes to reaching the goal of all human activity: The Good.


Fido, I may agree with you that the goal of all human activity is 'The Good'. But I disagree that it is to be found on the surface or at least can so easily be found or aquired or grounded in principle in our thoughts and consequently in our behaviour.

Also science reveals a world that is quite unlike the world as we experience it in daily life. When we look at or perceive a woman's breasts for example, we (or at least I) don't view clusters of skin molecules or atoms of carbon. When science looks in microscopically or looks out macroscopically what it does see and what it theorizes about seems far removed from what our daily realities are like.

And what about the detectives? Why would we need police detectives or Sherlock Holmes if everything were just as it seems upon the surface of things? Why do we need medical doctors with their scientific equipment etc.. So there must be a reality that the hard sciences hint of and that is only partially revealed to us in our crude daily lives.

I think we need the rationalist's philosophical method which we can use to peel back all of the layers of reality to let us bask in the ultimate power of existence, the fundamental purity of nature (which maybe something like God), and this method may be provided to us through the systems of Descartes, Spinoza or Leibniz, who are as rationalists claiming such a method. But the harder and deeper effort that is required must be tied to their method which appears to be essentially mathematical.

The point is that we are not at a high enough reality in our historical scientific development. Such a time will come when we live in virtual reality environments, when our environments become mathematized and thoroughly computerized and we will begin to see things as they really are, I beilieve. Until then we have to dream and visualize and press forward and try to get to a position where such truth lies.
 
Fido
 
Reply Fri 7 Dec, 2007 11:22 am
@kennethamy,
kennethamy wrote:
How, would you say, do we know that all dogs are animals, or that all bachelors are unmarried males? Or, that things equal to a third thing, are equal to each other? Or, even, that if I know that X is y, then I know that X is y is true? What did I sense, to know any of these?

Of the first, it is not only whether dogs are animals, but whether all dogs are dogs, which is to say not cats, or some other beast. We need to use all our senses to determine what things are as compared to what they appear to be, or are not, but appearance is first. If through no other method we learn identity through experience, which begins to build a catalogue through syllogism. Ultimately, to have some certainty we must destroy some dogs to compare them, first making certain they can be killed as all animals, and then finding in what ways they differ from other animals. Here is the rub: No matter how many dogs we show are animals we cannot ever be certain that all are. We always have to accept a standard of truth short of certainty, so it is not true at all. As Leibniz said: Iron does not float. But, iron boats float.

Of the second, this is cultural knowledge only true for a certain culture, but culture demands all the senses, and a cultural memory.

Third, As Leibniz points out; this can easily be shown with a balance scale, and to test the scale for true one must exchange weights on the scale. With this we are showing that gravity acts upon equal masses with equal effect. Clearly logic can push knowledge further into the realm of ignorence. Can we say, as in the example of the asymptotes that all things follow logically determined laws indefinetly? Without the ability to show what is true at any point we have no means to say what is true at every point beyond our grasp, so knowledge is gained by a very laborious process of pushing back the carpet of ignorence an inch at a time. Insight and creativity find a jimmy bar out of necessity. And it still has to be proved to be true.

Now, science is determined by senses, and senses are behind every scientific instrament. There is no science for justice, or virtue because these are not tangible qualities. Yet, with every scientific investigation we test what in general terms we can sense. What is the weight of a thing, what is its density, what is its shape, what is its temperature, what sound does it make, is it smooth or soft, does it have a charge, does it have a scent, does it decay, what is its color, what is its taste? Science is based upon tangible qualities that as we learn more of we can amplify, and measure more finely, and this is the basis of understanding and technology. We have evolved to our reality, and what is real is also logical. We do not invent logic, but discover it.
 
Fido
 
Reply Fri 7 Dec, 2007 11:59 am
@Pythagorean,
Pythagorean wrote:
Fido, I may agree with you that the goal of all human activity is 'The Good'. But I disagree that it is to be found on the surface or at least can so easily be found or aquired or grounded in principle in our thoughts and consequently in our behaviour.

We have been digging below the obvious world for a long time. I must ask: Did humanity not begin at some point with a conception of good to know what they were looking for?
Quote:

Also science reveals a world that is quite unlike the world as we experience it in daily life. When we look at or perceive a woman's breasts for example, we (or at least I) don't view clusters of skin molecules or atoms of carbon. When science looks in microscopically or looks out macroscopically what it does see and what it theorizes about seems far removed from what our daily realities are like.

Listen to you. When I look at women's breasts, for example. For example, when are you not looking at women's breasts, or for women's breasts to look at? You see, when we look at a thing in microscopia we do not lose the sense of the world it is apart of. That world, so unlike our world is still our world. I met a theoretical physicist once, and asked if he had a model of the universe. He replied with his German accent that he must confess he had no such thing. I thought. Why work with numbers if you think your numbers do not reveal some ultimate truth transending time and space? Is it not altogether certain that we are existing together on space ship earth, and that we share the same reality?
Quote:

And what about the detectives? Why would we need police detectives or Sherlock Holmes if everything were just as it seems upon the surface of things? Why do we need medical doctors with their scientific equipment etc.. So there must be a reality that the hard sciences hint of and that is only partially revealed to us in our crude daily lives.

I am not saying everything is just as it seems, but is as it seems. There is another layer of reality upon investigation, but we exhaust ourselves trying to find the ultimate reality. Trust me on this. My parent used to say of me that I took everything apart to see why it no longer ran. It runs, and the whole thing is the thing as well. Much of our investigation is aimed at doing nature one better. We have created some monsters with more in the crib. I would rather have a nature that works than one that is known, and does not.
Quote:


I think we need the rationalist's philosophical method which we can use to peel back all of the layers of reality to let us bask in the ultimate power of existence, the fundamental purity of nature (which maybe something like God), and this method may be provided to us through the systems of Descartes, Spinoza or Leibniz, who are as rationalists claiming such a method. But the harder and deeper effort that is required must be tied to their method which appears to be essentially mathematical.

And I think you should go back to checking chest sets. At least that is what it is about. There is no ultimate power. There is self control. There is observation. There is non invasive science. There are all the many qualities we cannot sense and cannot live without that have being only because we perceive their meaning. There are some realities, like some rooms, where it is better to go in through the keyhole of the mind than to go through the actual door. Every camera can be a trap to a soul. Keep your soul free.

Quote:

The point is that we are not at a high enough reality in our historical scientific development. Such a time will come when we live in virtual reality environments, when our environments become mathematized and thoroughly computerized and we will begin to see things as they really are, I beilieve. Until then we have to dream and visualize and press forward and try to get to a position where such truth lies.

You are definitely scaring the hell out of me. You are one of those -the grass is always greener next to the nuclear powerhouse guys aren't you? I am one of those -you don't get a better world by shetting all over this one- kind of guys.
 
kennethamy
 
Reply Fri 7 Dec, 2007 04:03 pm
@Fido,
Fido wrote:
Of the first, it is not only whether dogs are animals, but whether all dogs are dogs, which is to say not cats, or some other beast. We need to use all our senses to determine what things are as compared to what they appear to be, or are not, but appearance is first. If through no other method we learn identity through experience, which begins to build a catalogue through syllogism. Ultimately, to have some certainty we must destroy some dogs to compare them, first making certain they can be killed as all animals, and then finding in what ways they differ from other animals. Here is the rub: No matter how many dogs we show are animals we cannot ever be certain that all are. We always have to accept a standard of truth short of certainty, so it is not true at all. As Leibniz said: Iron does not float. But, iron boats float.

Of the second, this is cultural knowledge only true for a certain culture, but culture demands all the senses, and a cultural memory.

Third, As Leibniz points out; this can easily be shown with a balance scale, and to test the scale for true one must exchange weights on the scale. With this we are showing that gravity acts upon equal masses with equal effect. Clearly logic can push knowledge further into the realm of ignorence. Can we say, as in the example of the asymptotes that all things follow logically determined laws indefinetly? Without the ability to show what is true at any point we have no means to say what is true at every point beyond our grasp, so knowledge is gained by a very laborious process of pushing back the carpet of ignorence an inch at a time. Insight and creativity find a jimmy bar out of necessity. And it still has to be proved to be true.

Now, science is determined by senses, and senses are behind every scientific instrament. There is no science for justice, or virtue because these are not tangible qualities. Yet, with every scientific investigation we test what in general terms we can sense. What is the weight of a thing, what is its density, what is its shape, what is its temperature, what sound does it make, is it smooth or soft, does it have a charge, does it have a scent, does it decay, what is its color, what is its taste? Science is based upon tangible qualities that as we learn more of we can amplify, and measure more finely, and this is the basis of understanding and technology. We have evolved to our reality, and what is real is also logical. We do not invent logic, but discover it.


We need our senses to know that all dogs are dogs? (The sentence "all dogs are dogs" is not equivalent to the sentence, "all dogs are not cats" nor does it imply that sentence). All we have to know, to know that all dogs are dogs, is the general truth that All A is A, Of the law of identity. Which is a logical truth. For All dogs are dogs is a substitution instance of, all A is A. And all A is A is just a logical truth which we know a priori , which is to say, independently of our senses. There are no observations which can either confirm, All A is A, nor disconfirm, All A is A. And thus, no observations that can confirm All dog are dogs, or disconfirm, all dogs are dogs. If you can think of one, please let me know about it.
 
Fido
 
Reply Fri 7 Dec, 2007 06:05 pm
@kennethamy,
kennethamy wrote:
We need our senses to know that all dogs are dogs? (The sentence "all dogs are dogs" is not equivalent to the sentence, "all dogs are not cats" nor does it imply that sentence). All we have to know, to know that all dogs are dogs, is the general truth that All A is A, Of the law of identity. Which is a logical truth. For All dogs are dogs is a substitution instance of, all A is A. And all A is A is just a logical truth which we know a priori , which is to say, independently of our senses. There are no observations which can either confirm, All A is A, nor disconfirm, All A is A. And thus, no observations that can confirm All dog are dogs, or disconfirm, all dogs are dogs. If you can think of one, please let me know about it.

Don't you believe that to tell what a thing is you must be able to tell what it is not, what it is like, and what it appears like and what it is unlike? Dogs do have a lot of near relations and a great range of size. They may be all canines, but there the nearest part of their relationship ends, and even while each may appear like the other, appearances lie. Deeper study is always warrented.

Sir I wish not to offend thee in front of thy friends but thou art terribly full of it on the notion of identity. Identity is never proven, so it is not logical truth, but it is the axium upon which all logic depends. May I suggest that there is a great deal of difference between one standing on a bridge, and having a bridge standing on one. So, now we have Identity, in this case, as a predicate, that a dog is a dog. So how do we begin seeing if our dog is actually a dog when compared to the conceptual, and identical dog without reference to our senses? Let me ask you: If you saw a Jackel running around the streets of San Juan, would you know if it were a dog or not? How about a Fox? That tail is hard to miss. What do you know?

So, I would say there is nothing lawful about identity, and guess rather that it is a principal. And, I believe this is the point of syllogism, which is not strictly logical because it is not infallible, and that is, to establish an identity. And while I am disabusing you let me say something else. Mathamatical A, which is to say both logical and unreal identity together is not the same as a real identity. Dogs are inestimably more complex than A's. All A's are hypothetical. All conceptual dogs, as an identity are also hypothetical, but real dogs are anything but hypothetical. We live in the real world, and not in the perfect world of perfect concepts. But I would rather be a real dog in Puerto Rico than a conceptual dog in the best dog dictionary.
 
kennethamy
 
Reply Fri 7 Dec, 2007 07:02 pm
@Fido,
Fido wrote:
Don't you believe that to tell what a thing is you must be able to tell what it is not, what it is like, and what it appears like and what it is unlike? Dogs do have a lot of near relations and a great range of size. They may be all canines, but there the nearest part of their relationship ends, and even while each may appear like the other, appearances lie. Deeper study is always warrented.

Sir I wish not to offend thee in front of thy friends but thou art terribly full of it on the notion of identity. Identity is never proven, so it is not logical truth, but it is the axium upon which all logic depends. May I suggest that there is a great deal of difference between one standing on a bridge, and having a bridge standing on one. So, now we have Identity, in this case, as a predicate, that a dog is a dog. So how do we begin seeing if our dog is actually a dog when compared to the conceptual, and identical dog without reference to our senses? Let me ask you: If you saw a Jackel running around the streets of San Juan, would you know if it were a dog or not? How about a Fox? That tail is hard to miss. What do you know?

So, I would say there is nothing lawful about identity, and guess rather that it is a principal. And, I believe this is the point of syllogism, which is not strictly logical because it is not infallible, and that is, to establish an identity. And while I am disabusing you let me say something else. Mathamatical A, which is to say both logical and unreal identity together is not the same as a real identity. Dogs are inestimably more complex than A's. All A's are hypothetical. All conceptual dogs, as an identity are also hypothetical, but real dogs are anything but hypothetical. We live in the real world, and not in the perfect world of perfect concepts. But I would rather be a real dog in Puerto Rico than a conceptual dog in the best dog dictionary.


Of course you can prove that A is A. You can set up a truth table and show that it is a tautology. And therefore, it is a logical truth. ) All logical truths are tautologies, and all tautologies are logical truths. You do know what a truth table is. Don't you? The law of identity is one of three laws of logic. The others are: the law of the excluded middle; A or not-A; and, the law of non-contradiction, not both A and not-A. All the laws of logic are logical truths, and can be proved to be logical truths on a truth table. This is elementary logic.

You can google it easily enough, so you needn't take my word for it.
 
Fido
 
Reply Fri 7 Dec, 2007 09:53 pm
@kennethamy,
kennethamy wrote:
Of course you can prove that A is A. You can set up a truth table and show that it is a tautology. And therefore, it is a logical truth. ) All logical truths are tautologies, and all tautologies are logical truths. You do know what a truth table is. Don't you? The law of identity is one of three laws of logic. The others are: the law of the excluded middle; A or not-A; and, the law of non-contradiction, not both A and not-A. All the laws of logic are logical truths, and can be proved to be logical truths on a truth table. This is elementary logic.

You can google it easily enough, so you needn't take my word for it.

No; let's play this out for a few rounds. A dog is a dog, correct? Is a dead dog a dog? How about a small dog? What about a hot dog?
An orange is an orange, n'est pas? How about a navel orange? How about an osage orange?
Is a right a right? How about a common law right? How about a civil right? How about a property right?
Is an apple and apple? What about macintosh apples or road apples or rotten apples or them apples.
You said it yourself: that it cannot be proved or disproved. That fact makes it an axiom. That does not mean it is useless. In fact all our concepts are identities, and so, axioms. Are they any better than the reality they represent? Every example, and every phenomenon of a concept helps to prove the axiom if it does not disprove it. If a dog should be found that was in some senses like a cat or a cow, then it would tend to discredit the whole concept of dog. This dog's dog likes mice. He, and I use that term in the past sense sniffs them out, and tells me when they are around, and I dig them out, and he kills them dead. Now, he acts like a cat especially when the cat is around; but he smells like a dog when he is wet. I think he is a dog. My dog proves the concept.

You should think for a moment of how concepts are arrived at. Perhaps only a handful of people has added to our store of concepts, but all of us may modify their meaning. We learn concepts. They are, for the most part a form of cultural knowledge. We do not have to ask of reality: what is this? We learn because we are told, and while we may have to do some sorting out by way of the syllogism of what a thing has in common and what makes it distinct, still, most of it is given, tried and true, and only seldom confusing. Then we should ask: what have we that is original to our knowledge? In comparing knowledge to reality we discover the truth of the concept. Even though knowledge is, for the most part given, and, a'priori,- not in a metaphysical sense, but culturally, and so physically handed from person to person, and generation to generation, still we make it ours -to give, or discard after we test it against reality. If we say that every true concept is a bit of knowledge, then we can use it to begin a string of logic with which we may pull back the curtain of ignorence shrouding still greater knowledge. When we learn something new, we express that knowledge as concept, which is to knowledge like quanta is to energy, as a discreet bit of information on a certain subject.

For A is A, to be tautology it would have to be proven true begin with, and then it would have to be phrased as an argument without progress, such as A is A, because A is A, so there fore A is clearly A. Everything is for the best in this best of all possible worlds, after all. Whether A is A is exactly the point in contention with knowledge, and as a statement proves nothing.
 
kennethamy
 
Reply Sat 8 Dec, 2007 11:53 am
@Arjen,
Arjen wrote:
That, indeed, is a shame.

Replying to Pythagorean, NeitherExtreme, kennethamy and Fido:
When speaking of how information presents itself to us we cannot ignore the senses, nor the cognitive faculties. Both have a prt to play. David Hume, in his work "An Enquiry into Human Understanding", supports the opinion that if ever we have an a priori judgement on anything, it is made on the basis of a posteriori judgements of prior experiences or perceptions. He bases his thoughts on the fact that if we mean to structure things, we need prior information to compare our perceptions to.



Oh sure. That's why Kant in his Introduction writes that although all knowledge begins with experience, it does not all arise out of experience. We need experience in order to acquire our concepts. But that does not mean that we must have experience in order to know how those concepts are correctly connected. That every event must have a cause is supposed to be known a priori. Now, it is a necessary condition that we have experience to learn the concepts of event and of cause. The acquisition of concepts comes out of experience. But, one we have those concepts, how do we know (if we do) that every event must have a cause? It is that we know a priori. Kant makes the important point that synthetic a priori judgments are necessary judgments. What we know is that not only do all events have causes, but all events MUST have causes. Experience, Kant tells us, may teach us that all events do have causes. But how, Kant asks, could experience teach us that all events MUST have causes? There are no logical necessities in experience. Experience can teach us only about what is true, but not what must be true. The same is true of less controversial cases. Take, "All dogs must be dogs" (it is not just that all dogs are dogs). How did we get the "must" from observation? Perhaps we observe that all dogs are dogs, but how can we observe that all dogs must be dogs?
 
Fido
 
Reply Sat 8 Dec, 2007 03:07 pm
@kennethamy,
kennethamy wrote:
Oh sure. That's why Kant in his Introduction writes that although all knowledge begins with experience, it does not all arise out of experience. We need experience in order to acquire our concepts. But that does not mean that we must have experience in order to know how those concepts are correctly connected. That every event must have a cause is supposed to be known a priori. Now, it is a necessary condition that we have experience to learn the concepts of event and of cause. The acquisition of concepts comes out of experience. But, one we have those concepts, how do we know (if we do) that every event must have a cause? It is that we know a priori. Kant makes the important point that synthetic a priori judgments are necessary judgments. What we know is that not only do all events have causes, but all events MUST have causes. Experience, Kant tells us, may teach us that all events do have causes. But how, Kant asks, could experience teach us that all events MUST have causes? There are no logical necessities in experience. Experience can teach us only about what is true, but not what must be true. The same is true of less controversial cases. Take, "All dogs must be dogs" (it is not just that all dogs are dogs). How did we get the "must" from observation? Perhaps we observe that all dogs are dogs, but how can we observe that all dogs must be dogs?




First, most concepts are given by society. If you haven't invented a word it is unlikely that you have acquired any concepts on your own. We need experience to verify concepts, to cut open enough dogs in a sense to know that dogs are not something else. But cause and effect is a concept in itself, and it is one we do form at a very early age, that tends to re-enforce our sense of being, and being not alone. What the concept of cause and effect does not do is to illustrate the true state of affairs: that every effect might have multiple causes, and that every potential cause (each an effect) does not have an noticable effect. If you try to move a large body you may only weary yourself for nothing gained. Much energy is exhausted because it does not reach the threashold where work is performed. So, it is a concept. What then is the necessity of truth? Truth is the curse of philosophy because it stops it in its tracks. If the standard of truth is lowered to simple functional knowledge, then all one has to do is use the concepts we are given to look for truth in a particular sense. So, given a concept, cause and effect.



The truth is that not every effect 'must' have a cause, but every effect does have a cause if not a multiple of causes. Looking for a 'must' is totally inessential to the answer of the question at hand. It, necessity, is a metaphysical cul de sak. We have the conservation of momentum as a principal which works, is it not more sensible for some one who disagrees to prove an effect is not preceeded by a cause?. Cause and effect is an axiom. All concepts are axioms. They do not have to be proved necessarily true in every instance to give rational order to our existence. They simply focus our mind on the path before us. We do not need an absolute standard of truth to know reality. We may suffer to an extent of not trusting in our reasoning to push it too far into the future, but I trust- that if our minds are set free of the absolute weight of evidence which in the end contributes nothing to the absolute sense of truth, -that our insight and imagination will give us many possibilities to consider. Logic is a chain, and no one looks as foolish as one trying to push a chain that could be pulled. If reason illuminates the workings of our world. Fine. We do not gain in the process of applying it to the infinite as the priest of the middle ages did to God. It makes them look stupid in retrospect, and we should take the hint. Reason explains the past. We need necessity of truth to use reason to tell the future. Since we know enough to make the future, why bother to tell it?
 
kennethamy
 
Reply Sun 9 Dec, 2007 01:27 pm
@Pythagorean,
Pythagorean wrote:
In light of Leibniz's claims, I would like to know if anybody here thinks it is indeed possible that we are at all being deceived in our ordinary life in what we normally take to be reality? I mean, is everything that we 'experience' day to day just what it appears to be upon the surface? Isn't there at times a demand of effort made upon us to try and figure out what is really taking place at a certain time? Don't we have to inquire after a higher or more fundamental set of rules in order to seperate things true from things that are not apparent?

I mean, what is the use of philosophy if we believe that there's nothing under the surface that could furnish us with a brighter conception of their nature? And what is the purpose of science besides its practical benefits of improving health etc? Aren't we looking for the truth here?

If we are looking for truth, then the question arises as to how do we go about in the search; -?

Are we dreaming? It seems an important and perfectly reasonable question for someone to ask. And it seems to me that the way in which we attempt to answer this question is what makes us more or less 'empiricists' or more or less 'rationalist' philosophers.

The foundations of the Universe seem to be rational and they correspond to the reasonable, thinking person's mind. That is, I say, we are at one with the universe when we use our reason to formulate the laws of nature.

----------

[CENTER]"The human intellect understands some propositions, namely those of the mathematical sciences, quite perfectly, and in these it has as much absolute certainty as Nature herself. Of course the Divine intellect knows infinitely more propositions than we do, since it knows all. Yet in respect of those few which the human intellect does understand, I believe its knowledge equals the Divine in objective certainty--for here it succeeds in understanding necessity, than which there can be no greater certainty (Galileo Galilei, Dialogo sopra i due massimi sistemi del mondo, Ptolemaico e Copernicano, 1632). [/CENTER]


I would have thought that the sciences often show us that we are often mistaken (I would not say that there was a deception going on, for who would be doing the deceiving?) about surface appearances. Earth does not go round the Sun as it appears. Earth is not flat. Commonsense objects are actually composed of very small particles, atoms, electrons, and the like. And so on. So, don't the sciences tell us that "things are seldom what they seem. Skim milk often masquerades as cream."? (W.S. Gilbert).
 
 

 
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