What do Atheists Know? (A Repost)

[This article was originally posted in 2010; it seems pertinent to discussions of Skepticism today]

Do Atheists have evidence for their belief that there is no deity? What could possibly serve as firm, material evidence for a negative proposition such as that? If the evidentiary demands are not for physical evidence, then what sort of non-material (aka super-natural) evidence do they embrace?

As with all things Atheist, there is no common assent to any specific philosophy or even modus operandi. Every Atheist is allowed, and is generally even proud of, his own freedom to create his own philosophy, his own ethic, his own worldview, his own reality and truth. (Well, maybe not truth, some claim that it is true that there is no truth.) In formal debate situations, Atheists will limit their admission of the possibility of real knowledge to be restricted to material, physical knowledge. This knowledge, they will say, is verifiable; no other type of proposed knowledge has this quality.

Is verifiability a guarantee of knowledge of reality? Is it the most fundamental property of truth? If we declare that it is both the fundamental property of truth and a guarantee of knowledge of reality, how do we know that? How is that declaration verified, itself?

The question, “how do we know that” leads to either a circular argument, an infinite regress, the need for basic foundational principles, or the concession that we can know nothing. Circular arguments and infinite regressions are unsatisfactory. Basic foundational principles are arguable, even deniable. That leaves us with the inability to know anything with any certainty at all: radical skepticism.

Radical Skepticism exists based on the rejectability of virtually everything, due to the potential falsity of all input, including sensory (external) input that is our window to the world outside our selves. Radical Skepticism especially rejects internal sources (experiential, intuitive, reflective, abstract) which derive from our own mental activity. Let’s take some examples.

The Problem of Evidence
Did Bertrand Russell exist? How can I know with assurance? What is the evidence, and how is it validated?

Direct Evidence: There is none: The existence of Bertrand Russell has reputedly ceased. But even if he were still (reputedly) alive, and we could touch and hear a person reputed to be him, that sensory input is suspect, as will be shown below.

Indirect Evidence: There are historical accounts regarding Russell: But history is not reliable. And there are Russell’s writings: books, letters and speeches with “Bertrand Russell” attributions; but are these really written by someone called Bertrand Russell? What evidence is there that proves the validity of this evidence? An infinite regress is required here: how do validate the evidence that is used to validate the original evidence?

Photos: Is this man Bertrand Russell? Really? For certain? Says who?
Witness testimony is notably unreliable.

Both sensory perceptions and internal ruminations are rejectable as potentially erroneous and flawed sources for valid information about anything to be known with certainty.

If we can’t know anything for certain, can we Know that we can’t know anything? For certain?

Brain in a Vat: Destruction of sensory knowledge as a valid source.

The idea behind a Brain in a Vat is the speculation that I might exist in a false universe, one that is created and exists only in my mind. Descartes posited a meddling demon controlling our minds, while the more modern idea is that a horde of scientists are feeding my vat-bound, detached brain with all the neurological signals that make me think that I am interacting with a universe that does not actually exist. Even the date and time are false – the scientists and my actual brain exist far in the future, while my neural inputs make me think I am in the 21st century. Everything I experience is false, a fantasy simulation that is maintained by the myriad scientists feeding signals into my brain.

How am I to prove, conclusively, that this is not the case? What evidence can I produce and submit to myself that will be adequate to invalidate this idea with absolute certainty?

G.E. Moore raised a hand; “here is a hand”, he said, then, “here is another hand”. Moore’s point was that some things are undeniable. How is that possible? Moore could have been a brain-in-a-vat, or possibly part of my own brain-in-a-vat simulated but false experiences. What exactly determines deniability?

Traditional concepts of evidence are wholly inadequate to vanquish this problem: there is no way to prove that the brain-in-a-vat is false. Yet we don’t believe that to be the case. I have never met anyone who thought he was a brain-in-a-vat, and that I was merely a simulation for him to experience in his brain.

Further, there is no evidence to actually support the concept that I am, in fact, a brain-in-a-vat. It seems obvious that I am able to direct much of my experience myself. I am able to go, at will, to incredibly detailed places, such as giant stores with myriad products that I can touch and manipulate; I can trek to wilderness areas with incredible panoramas of flora, fauna, and geology; there are billions of people that I can interact with in complex modes. There seems to be a limitless unboundedness to this simulation. Plus, I have a strong sense that if my free agency does not exist, then I do not exist. I am not an automaton, performing previously established tasks. Yet I cannot prove this belief.

Can Knowledge Exist?
If nothing can disprove the idea that existence as I know it is really a simulation and not real at all, then how can I know anything? What is certainty, anyway? What is the nature of knowledge and how is it validated sufficiently to be allowed as an acceptable belief?

Original Empiricism, Common Sense, and Worldview Assembly.
Perhaps I am, in fact, living in a simulation. What can I know about it – what are the characteristics of my environment, whether simulated or real? How would the process of knowledge acquisition and validation differ from that required if I lived in actual reality?

It would all start with observation, in either reality or simulated reality. What can I observe about the universe that is useful in helping me to understand and deal with it? Is it consistent? Is it contradictory? What elements within the universe determine my abilities to live, to think, and to cope with my environment? Observation is the original empiricism: basic knowledge is that experience which we encounter frequently enough that we grant its existence as real, or at least real enough to expect its existence and recurrence. Babies differentiate between women in general and Mommy by having experienced a relationship between the specific Mommy person and a full stomach, after having expressed the distress of the hunger experience. Observation of repetitive experiences generates expectations of consistency.

We might come to think that the consistency that we find in our universal environment tends to discount the idea of hordes of scientists feeding us simulation data; there would surely be a rift in the consistency of such a system at some point. Even the ability to test the simulation from within the simulation, destroying pieces of it here, creating new things there, leads to discounting the idea that my universe is not real. What about creating sub-simulations? Or Meta-simulations? At what point is a fantasy disputable enough to discount it altogether, even without the ability to produce physical evidence of its non-existence? Or perhaps, at what point is it necessary to care whether I am living in a simulation or in physical reality? If one is indiscernible from the other, what does it matter, at bottom? And if this is so, then skepticism, especially radical skepticism, has no force.

And very specifically this exercise shows that knowledge is generated by a free agent mind, through observing, cataloging and judging any and all inputs to the mind, regardless of the source. It is the faculty group within the mind, operating on experiences received by the mind, that determines what can be accepted as knowledge and what is to be rejected as fallacy. It is not the input source that makes the determination: it is the mind.

Source of Experiences
Along with the obvious external neural feeds from the environment, are there any other experiences that can generate knowledge? What would the source of such experiences be? For example, working a mathematical solution to proposed mathematical paradoxes: where does this experience come from, if it is not generated as a physical object (or a simulated external object)? Is it the molecular composition of nerves, or the electrochemical discharges that are producing this knowledge? Is there any reason to view molecules or electron/ion flow and declare, this will produce higher mathematics? Or empathy? Or green? Or knowledge in general?

The brain is molecules and electron/ion flow and blood flow. It is the mind that resides on the brain that produces rational categorization of experiences which turns into knowledge.

Locke’s hypothesis of the faculties of the mind still stand, except perhaps amongst the chronic skeptics, many of whom deny even consciousness. Locke proposed that the mind (being a blank slate in terms of original knowledge) had the faculties of apprehension, comparison, differentiation, judgment, and comprehension. These, along with various types of memory, form an operational basis for rational assessment of one’s environment. They form an internal intellectual system for generating and validating experiences as knowledge.

If this is so – and there is no non-chronically-skeptical reason to think it is not so – then knowledge is not determined solely by externally replicated experiences. Knowledge also comes from non-sensory sources, too.

What are the principles used by the faculties of differentiation and judgment, and what are their sources? Do these not require the same consistency and coherence mentioned above?

It seems that consistency and coherence are basic requirements for knowledge, for the ability to know anything and to judge its certainty. In fact, they are known as First Principles.

I recently came across a website that, along with being Atheist, rejects Boolean logic and the First Principles. This apparently is predicated on unknowability principles that are now emplaced in mathematics, those theorems of Godel, and the intuitionist logic of Brouwer, which displaces much of standard mathematics with philosophy based on unknowability presuppositions. But these arguments cannot defeat the standard objection: if one can’t know anything for certain, then one can’t know with certainty that he can’t know anything for certain. This paradox is a logical defeater, but under the radical skepticism principles, paradoxes don’t prove anything either, since logic is unknowable or at least unprovable. So logic doesn’t exist in the world of such skeptics.

The skeptic’s position of unknowability does not match up with observable knowledge. It is observable that the universe, whether real or simulated, is consistent in its behaviors according to physical laws; that the laws are coherent; and that we can know that, within the limits of induction. We can also know that there are limits to inductive certainty, and that with a huge number of observations of consistency, the certainty, while still not complete, is higher than the certainty of unknowability. Observations trump philosophy, when the philosophy is not congruent with observations.

It has been observed that skeptics do not behave in a manner consistent with their philosophy. Skeptics do know that the bus is coming and they do not step in front of it in the belief that their senses are faulty. They do not step off of balconies or the edges of cliffs. They do eat food, drive cars in abeyance of the hazard of other vehicles on the road, some even have sex and raise families just as if they actually exist. This failure to behave within the belief system is pointed to as philosophical hypocrisy by dissenting philosophers of the “reality” bent.

Yet in order for a materialist to salvage a system of beliefs which cannot be proven valid, such as Atheism, one must assert unknowability for at least some of the experiences and philosophies encountered (not his own of course).

And there it stands, they mired in illogic while being forced to assert that there is no logic, it being unknowable. The rest of us have to proceed without them, in the knowledge that knowledge is possible, rationality is possible, it being based on fundamental principles that are observable in the universe, and which are useful in developing rational worldviews, rather than basking in non-coherence while rejecting coherence as a valid principle. It is one thing to declare oneself and ones position as being rational; it is another to define rationality, to accept its existence, and actually use rationality in creating ones position.

Note: Some of this is based on ideas in Michael Huemer's book, "Skepticism and the Veil of Perception": highly recommended.

Originally Posted by Stan at Tuesday, November 16, 2010