The Senses as Necessarily Valid

Epistemology is the branch of philosophy that studies the nature and means of human knowledge.  The field lays out the rules and principles to guide the formation of concepts, the construction of logic, and generally how to gain knowledge and show its validity.  Objectivism holds that metaphysics and epistemology combined are the theoretical base of any philosophy.[1]

There is a little more context needed than metaphysics to fully confront the issues in epistemology. We must first discuss 2 topics that make the field of epistemology possible: sense-perception and volition (free will).  I’ll also cover the axiomatic concept of “self” at the end of this series, as I think it’s a subject that needs to be discussed for a complete understanding of Objectivism.

Now we can begin with the role and validity of human sensory-perception.

The Primary Form of Consciousness

Before I discuss the intuitive validity of the senses, I will give a philosophical perspective on sensory perception, in large part thanks to our advanced scientific age.  (In particular, thanks to the discoveries and theories in the fields of anatomy, physiology, biology, and neurology.)

The senses (sight, hearing, taste, touch, and smell, among other senses that other animals possess) are forms of experience produced by physical entities acting on our physical instruments: our sense organs.  Our sense organs transmit information from the world to our nervous systems and brains, following physical laws.  They do not possess the power to distort, to invent, or to deceive.  They don’t create a response from nothing.  They only react to something that exists which acts on them.

Additionally, the senses do not interpret or identify the objects that act on them; they are merely part of a stimulus-response reaction.   We only become aware that the objects exist, not what they are.  Ayn Rand stresses this point by comparing the senses to the “identifying” role of reason:

The task of [man’s] senses is to give him the evidence of existence, but the task of identifying it belongs to his reason, his senses tell him only that something is, but what it is must be learned by his mind.[2] 

The senses are an automatic means to awareness of some aspects of existence, and so they cannot err in this role.  The senses are “error-free,” as Aristotle was the first philosopher to note.[3] (This is Objectivism’s general answer to the problems of the senses advanced by philosophers throughout history.) 

While the senses do not err, the conceptual level of consciousness certainly can.  We can see a man and mistake him for a friend named Bob when he is really a stranger: such a decision would be an error in thinking, not in perception.  Our judgments about the things that we perceive can be mistaken, but not the perceptions as such.

Everything else our consciousness does flows from the direct evidence of the senses (e.g. thought, memory, imagination, evaluation).  For this reason, Objectivism holds that it is our primary form of consciousness.[4]

Perception as Condensation

Objectivism does not bemoan the limits of the senses, but notes their power.  Their function is to compact intricate facts about reality, with the result being that the information comes to our consciousness in the form of a few sensations.  With our sensation of touch, for instance, we experience facts like pressure changes, temperature changes, and bodily damage as weight, heat and cold, and pain.  Indeed, the senses give us the first evidence of these physical facts, which allows us to later discover more and more general laws of reality.

The relevant point here is that our sensations are caused partly by the complex facts constituting the objects in reality, and also caused partly by our organs of perception.  The combination leads to our perceptions being in the forms of color, brightness, sound, smell, touch, and taste (among other sensations).  A being with different types of sense organs would perceive reality in correspondingly different forms, such as snakes being able to perceive infrared light.  (Infrared light is normally invisible to the human eye.[5])

Different living beings with different sense organs gain differing amounts and kinds of evidence of existence.  So long as the beings have minds that can interpret and investigate the data of the senses, the differences in sensory forms will not affect the ultimate conclusions reached about the laws operating in reality, merely the order of the scientific principles leading to the fundamental laws.

The Validity of the Senses

Having described sensory perception and the function the senses serve, I will now discuss their validity.

I’ve stated repeatedly that the basic axioms are validated by sense-perception.  We perceive that things exist and are what they are, and our perceptions are our first means of grasping our own consciousness.  So, how do we grasp the validity of the senses?

The validity of the senses is a corollary axiom, stemming from the fact of consciousness.  Sensory perception is the primary form of consciousness: in affirming the consciousness axiom, we also affirm our means of awareness, i.e. the senses.  The validity of the senses then is a self-evident implication of the fact of consciousness.  If consciousness exists, then so must the data provided by the senses, our main source of awareness.[6]

Like the basic axioms, the senses’ validity does not admit of proof and precedes issues like proof.  Strictly speaking, a proof takes a theory or idea and traces it back to the data given by the senses.  Due to this, the data of the senses themselves are incontestable; they must be the foundation upon which any successful proof must terminate.

And this is not just an affirmation of human perception alone, as Peikoff stresses:

If a ‘valid’ sense perception means a perception the object of which is an existent, then not merely man’s senses are valid. All sense perceptions are necessarily valid. If an individual of any species perceives at all, then, no matter what its organs or forms of perception, it perceives something that is.[…][7]

No kind of sense perception can take in everything about reality.  There is a limit to what any given sense organ can process, and so the ability to detect certain aspects of reality precludes the processing of other facts, which would require different sense organs.  The point is that any facts that the senses can deal with are facts, i.e., are data that a given consciousness uses for awareness.[8]

References

[1]: Leonard Peikoff, Objectivism: the Philosophy of Ayn Rand (OPAR), p. 43.

[2]: Ayn Rand, Atlas Shrugged, p. 942.

[3]: Aristotle, De Anima (On the Soul), book II chapter 6, 418a; chapter 7, 419a; and book III chapter 3, 428b.

[4]: OPAR, p. 45.

[5]: Scientists recently found a case in which the human eye can see infrared light.  See here: http://news.wustl.edu/news/Pages/27742.aspx

[6]: OPAR, p. 45.

[7]: ibid., p. 46.

[8]: I’ll handle various objections to the senses and volition/free will once I’ve finished this series of posts, similar to my “Objections to the Axioms” series.