Skepticos

It has been a few years since I studied any aspect of Objectivism (Rand's variety), and I am not sure why I thought of this the other day, but I did. Anyway, I am asking the Objectivists (or anyone familiar with Objectivism) who post here:

Given the fact that Objectivism adheres to perceptual realism, what argument does Objectivism employ to demonstrate the validity of the senses? If any?

Just curious to hear, and thanks for your time!

- Skepticos

Keith Russell

Greetings:

Objectivism views the validity of the senses as axiomatic.

If the senses aren't valid, by what means would one be able to discover/know it?

Keith.

Primal

I've always wondered what was meant exactly by the validity of the senses being axiomic, one reason being that sensations were supposed to form the basis for knowledge, however this justification seems more conceptual. Also this ignore the fact that sense expereince is contextual, whereas as axioms are more absolute.

Likewise, again what does this mean? Sensation can be valid, in the case of perceptionism, and yet fail to tell us anything about an external world, or even admit that such a world exists. In such a case sensation would be reality.

Also, if sensations are axiomic, then how can they sometimes be wrong in the case of hallucinations. I know Objectivists say "sensations are disproven via latter sensations." However such an argument suffers from this difficulty: in that sensations, rather then disproving eachother, can merely be changing reality or indicate a radically changing reality. In order to say one sensation disproved another one has to utilize conceptual standards.

I always saw this formula as working better 1) There is an external world-conceptual axiom. 2) Our sensations usually tell us about this world. Though they can make mistakes and must be checked by further sensations and comparison to background knowledge.3) The properties of the external world do not alter or change radically. Radical change is indicated by background knowledge, in that certain properties are deduced by certain other known facts.

I.E. Given what we know of solids and water, it is unlikely water can bend a pen. Hence when I see the pen bent in water, this must be an illusion, and checking the pen with my fingers verifies this.

elwoodblues

Essentially, yes. Though putting things so simply would put a lot of philosophers out of a job

Keith Russell

Primal said:
I've always wondered what was meant exactly by the validity of the senses being axiomic, one reason being that sensations were supposed to form the basis for knowledge, however this justification seems more conceptual.

Keith: Its axiomatic because you cannot reject the evidence provided by the senses, without first referring to the senses and the data they provide.

Primal: Also this ignore the fact that sense expereince is contextual, whereas as axioms are more absolute.

Keith: Contextual? In what way is sense data not absolute?

Primal: Likewise, again what does this mean? Sensation can be valid, in the case of perceptionism, and yet fail to tell us anything about an external world, or even admit that such a world exists.

Keith: I disagree. Even if we were brains in jars, receiving piped-in sensations, we are receiving sensory perceptions externally, and so the senses do reveal that an outside world exists. The sense data would not necessarily correspond accurately to this external world, but I believe that they do guarantee its existence. (Remember, our brains exist in that world whether in our heads, or in jars in shelves.

Primal: In such a case sensation would be reality.

Keith: I don't understand. I thought you were looking for ways in which sensations would not reveal reality.

Primal: Also, if sensations are axiomic, then how can they sometimes be wrong in the case of hallucinations.

Keith: If you can trust your senses enough to know that there are hallucinations, as opposed to accurate visual perception, there you go.

Primal: I know Objectivists say "sensations are disproven via latter sensations." However such an argument suffers from this difficulty: in that sensations, rather then disproving eachother, can merely be changing reality or indicate a radically changing reality.

Keith: But, to believe that (at least rationally), there needs to be some evidence to support it. Otherwise, how do you know its true? Or, why even suppose that it might be true?)

Primal: In order to say one sensation disproved another one has to utilize conceptual standards.

Keith: The senses don't disprove one another, they help to validate one another. If you 'see' a mirage, and yet you feel no water, and taste only dirt, you did see a refraction in the atmosphere that looked like water. The problem isn't your sense of sight, but how your consciousness interpreted what you actually did see. You really did see something, and you incorrectly interpreted it as water.

Primal: I always saw this formula as working better 1) There is an external world-conceptual axiom. 2) Our sensations usually tell us about this world. Though they can make mistakes and must be checked by further sensations and comparison to background knowledge.3) The properties of the external world do not alter or change radically. Radical change is indicated by background knowledge, in that certain properties are deduced by certain other known facts.

I agree with 1. 2 has the problem of assuming that the senses make mistakes, and I'm not sure I agree. We'd have to define what consitutes 'mistakes', in a sensory sense. That takes us away from metaphysics and epistemology, and into the realm of physiology and biology. 3 is a huge problem, since the external world changes constantly, though only ever according to its nature.

Primal: I.E. Given what we know of solids and water, it is unlikely water can bend a pen. Hence when I see the pen bent in water, this must be an illusion, and checking the pen with my fingers verifies this.

Keith: Not only that, but when you take the pen out of the water, it is not bent. Also, you can measue the refraction, and thus know that your eyes did not deceive you; it is the light (carrying the image of the pen to your eyes) that is bent, not the pen itself, as the light travels through water.

Keith.

Primal

What about hallucinations then? Or a mirage in the desert? Must I actually go out there and check if it's a mirage. And then what about dreams?

I know you will say "sense data issimply correcting sense data". However on what basis os it correcting instead of remaining compatible? What if reality is simply changing with sensations.


Hallucinations. I can take a hit of acid and see the grass change colors, however I know this is not really the case. Hence I know my sense data is flawed in this case, hence it is contextual-checked by other sensations, bakcground knoweldge etc. meaning sense data is not taken at face value.


How so? In this case I would say it was reasoning that made sure these things existed not sense data. Where is the sensation that says' reality is external." None really, if sensation was taken at face value we would not know reality was external, all we would know is that we recieve certain sensations.

Yes, I agree here but this conclusion is not justified by mere sense data alone. Reasoning estblishes that fact and places a check on sense data. We could not sense that even if our brains were in jars there would be an external world, no sensation indicates this. This conclusion has to esyablished conceptually without sense data.


No, I am merely showing how sensation alone cannot establish the fact that reality is objective. That is conceptually axiomic, more so then sense data. Perceptionism merely illustrated this.

The problem in this case is one of correletaion, how do we know our senses accurately report what is outside or tell us that there is even an external reality at all?

The only strictly empirical way to know this is by apealing to sense data and hence establishing sense data via more sense data. The argument is circular, and neglects the fact that if sense data is our only means to describing reality, then it is reasonable to say sense data is reality. To say otherwise is to invoke concepts and through off empricism.


But this begs the question, how do we know the hallucinations were not accurate? What if there really was water there, in the desert, as long as I saw it. And then for some reason I just stopped percieving water it dispeared. I.E. What if my sensations determine reality?

To say that the hallucination was inaccurate despite it being a sensation, is to presuppose that there is a conceptual axiom that overides the sensory axiom. i.e. that reality is not necessarily what is percieved. Given this sensations can longer be said to be the sole basis or most fundamental axiom of knowledge.

Well in this case the proof would be sensations. "The pen bends in water, but straightens when it leaves the water. This is true, can't you see it?" Or "Alien abductions do happen, I have experienced them first-hand, I know they happen." The only way to eliminate such fantastic experiences as actual evidence, is to suppose, axiomically, that background knowledge takes precedence over this, and that Occam's Razor does is well. Such principles are conceptual, not just a matter of evidence.

Or maybe it's special water, too thin to be felt. Or maybe it's your sense of taste and touch that are deceptive instead of your eyes.


Yes, I was getting to this. Sensationsmust be accompanied by interpretations. These interpretations I believe, often take precedence over immediate/singular sensations.

Well from a biological and physiological viewpoint, they seem to be working fine. From the standpoint of the senses proximate function, detecting lightwaves for eyes, they are still working fine. But from the standpoint of ultimate functions, i.e. accurately describing reality, they have failed in this case. And they may fail totally, that is possible, though unlikely. What makes this unlikely? Conceptual standards.


For the strict empricist it is, but not for a foundationalist. Radical change in such a foundationalist system that allows for concepts can be removed 'a priori' via Occam's Razor and the precedence of background knowledge.

This would be radical change not barred via pure empiricism.


But refraction cannot be measured directly or by all, this would require generalization to all pens, as well as decution via the pens look the same so they will behave the same way.

If such conceptual standards are removed, and sensation is dominant, then one can say the pens do bend, and refraction is right when studied, saying perceptions merely changed instead of conflicting. Immediate sensation would take precendence. Also can we percieve refraction? Only indirectly, and that requires we make an inference, but how can an inference be made save for conceptual mechanisms and reasoning? Inferences are not acts of pure perception.


The main problem of tabula rasa empiricism is that it cannot even establish itself as was shown by the logical positivists.

The main empricist standard is the principle of verification i.e. the claim must be reduced to sense experience to be true. The problem is though that such a principle itself cannot be reduced to sense experience.

Empricists say all knowledge comes from sensation, but is that claim itself a matter of sensation? I have seen no thing that says "sensation is the ultimate standard."

Hence sensation is not likely to be the ultimate axiom, such a thing is more likely conceptual. I would say sensation is axiomic in the sense that it is very basic and cannot be reduced to anything else. However sensation is dependent on concepts for its validity and to check it's accuracy at any given time. Not to say the matter is one of clear cut context vs. sensation, as the two may often blend. As is the case when comparing background knowledge to current testimony or experience.

Skepticos

So, let's see if I understand this correctly.

Objectivism holds that the validity of the senses is axiomatic, for any attempt to undermine them is self-refuting. This is due to the fact that any attempt to undermine the senses is comprised of conceptual knowledge, the latter being wholly derived from the data provided by the senses. And if the senses are invalid, or its validity is in question, then all conceptual knowledge, which is founded on the data provided by the senses, is equally invalid, or its validity is in question. Thus, to attack the validity of the senses is tantamount to refuting the refutation.

Is the position of Objectivism?

- Skepticos

Primal

I to my knowledge think you have it right Skepticos and know quite a bit about Objectivism myself. I have read most of Rand's books and have the "Ayn Rand Lexicon" for example.

In any case I think it's important to differentiate between a specific sensation, as well as it's validity and sensations as a whole.

I do believe that sensations as a whole are established axiomically via as self-evident. Their existence in any case is not really open to reasonable doubt. However to say that they pefectly describe reality at all,most of the time, none of the time or rarely is another matter entirely. As is the question of whether a specific sensation describes reality well at any given time. I think it is reasonable to conclude that sensations work most of the time, this seems axiomic, though provisional.


As for establishing the validity of any correspondence at all, I think this is axiomic but that the alternative is not necessarily self-refuting. It is only self-refuting if the criticism of correspondence is based on sensations at all, and the sensations are the evidence. I can using logic and concepts alone reject all or most correspondence without any logical trouble.

Keith Russell

Ayn Rand said that sensations (percepts) tell us that something is, but they don't tell us what something is.

For that, we must use reason.

Keith.

Skepticos

Well, thanks for the input from all of you. I feel as though my question was answered to my satisfaction.

- Skepticos