Recently, in a discussion with a fairly dogmatic professor, I mentioned in passing that "I am a bit of an empiricist," and his response was "Well, I hope you aren't since empiricism is false!" Beyond this, he offered no real explanation.
My question is: Is this true? Is it "false" in some categorical way?
Thanks
The argument against empiricism is that a proper accounting of how we are able to acquire knowledge requires information beyond that which the senses can provide. Kant, for example, argues:
"These are the conceptions of space and time as forms of sensibility, and the categories as pure conceptions of the understanding. To attempt an empirical deduction of either of these classes would be labour in vain, because the distinguishing characteristic of their nature consists in this, that they apply to their objects, without having borrowed anything from experience towards the representation of them." Kant, Critique of Pure Reason
One finds that abstract notions are required for even the most basic functions of perceptions, such as basic notions of logic, recognizing objects, making comparisons, etc. I've found that even those who claim to be empiricists have a hard time avoiding this issue. Quine, for example, makes the following observation about our ability to make comparisons:
"A standard of similarity is in some sense innate. This point is not against empiricism; it is a commonplace of behavioral psychology." Quine, Natural Kinds
What I find surprising about Quine's statement is that it leaves me wondering what he believed a non-empiricist would attribute innate notions to that couldn't be classified under some branch of psychology. If a rationalist and empiricist both were to attribute innate ideas to the workings of the mind, in what way does he distinguish his position as empirical?
Kant, as a good example of a non-empiricist, also attributed certain notions to the way the mind functions, and thus they might be classified as psychological phenomena:
"But to show reasons for this peculiar character of our understandings, that it produces unity of apperception a priori only by means of categories, and a certain kind and number thereof, is as impossible as to explain why we are endowed with precisely so many functions of judgement and no more, or why time and space are the only forms of our intuition."
Some arguments
There are various reasons why abstract notions either are not or cannot be communicated by the senses:
People often have difficulty appreciating the truth of these assertions because they involve notions that are so basic to our understanding of experience that it's difficult to imagine what experience would be like without them.
No, empiricism isn't categorically incorrect. Your instructor's position is called naïve dualism:
We labeled this pattern of responses “naïve dualism.” This is the belief that acts are brought about either by intentions or by the physical laws that govern our brains and that those two types of causes — psychological and biological — are categorically distinct.
Dualism of all sorts was far more common historically. By the late 1900's, we see a tipping point, where people who study intelligence (either artificial intelligence in the context of Computer Science or human intelligence in the context of Neurology) have rejected dualism while more classical figures such as John Searle continued to offer flimsy arguments in its defense.
To see this contrast, I'd recommend checking out the paper in which Searle publishes his Chinese room thought experiment: Minds, brains, and programs (1980). Halfway through the PDF, there're responses from people in other fields, such as Computer Science, sharply criticizing Searle's position.
People who work with intelligence research have had to reject dualism because believing in it limits one's understanding of intelligence itself, preventing one from being an effective researcher. But for people who don't need to understand neural networks, believing in dualism can be comforting; it comes with feelings of absolution and certainty, as internal knowledge stands above all empirical doubt.
Anyway, from the non-dualist perspective, all observations are empirical; even if you think "1+1=2", you're observing the consequence of your neural firings, rather than divining some grand cosmic truth. The dualist position that your instructor advocates would like to claim that such internal observations are fundamentally distinct, but, again, that argument falls apart when we start researching how the brain works and creating new minds, i.e. AI.
An older analog of dualism was called vitalism. Vitalism was basically this idea that living creatures had something special about them, e.g. Élan vital, which is analogous to the something special about intelligence that dualists believe in, qualia.
If you put yourself into the historical mindset, vitalism probably made a lot of sense to people of the time. Life seems distinct from non-life, so presumably there's some fundamental, irreproducible cause of that, right? That vital spark. Today, dualists see intelligence the same way. There's that something special about it, that fundamental, irreproducible cause - qualia.
Over time, the development of biology discredited vitalism. Neurology and AI are doing the same with dualism.
Addressing this question from a computational point of view, research into machine learning has shed a lot of light on the questions concerning the prerequisites of learning. In particular, the No Free Lunch Theorem is the result of an attempt to quantify the amount of prior knowledge required for extracting information from data. This theorem is described as follows:
"The No Free Lunch Theorem Of Optimization (NHI) is an impossibility theorem telling us that a general-purpose universal optimization strategy is impossible, and the only way one strategy can outperform another is if it is specialized to the structure of the specific problem under consideration." Yu-Chi Ho, Simple explanation of the no free lunch theorem of optimization
This might be formalized in logical notation as follows:
∀xyz[(Sxz & Syz & P(x) > P(y)) → Cxz]
From this, it's fairly easy to conclude the following:
∀xz[(~Cxz & Sxz & P(x) > 0) → ~Ǝy[Syz & P(y) = 0]]
Translation: Without any prior knowledge of a given type of problem, if a strategy for that type can be expected to be successful, it must be assumed that there exists no strategy of the same type that consistently fails.
What's interesting about this is that the strategy in question is pitted against others of the same type that is not distinguished from it in any way. In other words, such strategies are generic applications, and the No Free Lunch Theorem teaches us that the expectation of success depends on the assumption that the particular type of problem in question must be solvable with equal probability by any generic application. Therefore, from a purely empirical perspective, it must be assumed that the initial stages of learning are of such a type that any generic strategy will have a greater than random chance of success. Otherwise, empiricism is false.
That's really a huge assumption to make when it's remembered that all machine learning programs have certain assumptions programmed into them. The designers of such systems don't expect the machine to learn, for example, that data contains information or that concepts can be extracted by comparisons and other logical operations. In other words, there is no such thing as a purely empirical AI program because they are always hard coded with some basic a priori knowledge. Consequently, it's unimaginable what such a generic strategy could possibly mean if it is supposed that it consists of none of the assumptions hard-coded into current machine-learning programs.
Consider the fact that machine learning programs are themselves specialized for a particular type of problem, viz. to those in which there is something to be learned. Therefore, they cannot be considered generic in the sense described, so a program which is generic would be one that is not specialized for learning at all. This idea can be formalized by specifying the type of problem as learning and applying it to another consequence of the No Free Lunch Theorem:
∀x[(~Cxn & Sxn & P(x) > 0) → ∀y[Syn → P(y) > 0]]
Translation: If a strategy for learning can be expected to be successful without presuming anything about the nature of learning, it must be assumed that every strategy not specialized for learning would be just as likely to succeed.
This would lead to the absurd conclusion that all algorithms would have to have a better than random chance of learning. Of course, that can't be the case, so any effective strategies must incorporate some prior knowledge about the nature of the problem. In other words, there's no such thing as a generic solution that can be expected to have anything better than purely random success in any task. Any child born with such a system might have a random chance of doing something right, but it could hardly be recognized as learning. Therefore, either the No Free Lunch Theorem is false or empiricism is false.
I don't know the context of your conversation, but "empiricism" can refer both to a historical position in a philosophy and a general epistemological attitude.
The historical position is false (or at least a common understanding of it is). Specifically, the foundationalist version of empiricism which claims roughly that
all knowledge is that which comes from the senses (Cf. wikipedia's definition)
This is demonstrably false. Specifically, it does not work insofar as the truth of this sort of sentence or laws of nature are not themselves derived from the senses. There's a lot of variations on this argument -- but as long as at least one stands, then foundationalist empiricism (empiricism which admits no other source of knowledge than the senses) is false). We can find a more elaborate argument against it in Hegel's preface to the phenomenology of spirit under the title "Sense Certainty"
Now that being said, this is as much a convenient falsehood as Descartes "radical skepticism" and "brain in a vat." In other words, it's not even clear if there's anyone who ever held the view in the easily pilloried form.
Presumably, when you say you're a bit of an "empiricist" what you mean is something more to the effect that you think knowledge comes from the senses. Or perhaps, you use it as a shorthand denial of Platonic forms and the like. The idea that our knowledge comes from the senses has a diverse following that includes both Aristotle, Locke, Mill, Quine, Searle, and others. (Note here that there's no "only" -- as many (all?) of these views think there's some processing and other things that are involved in knowledge).
See also https://plato.stanford.edu/entries/rationalism-empiricism/#1.2
