These observations are implied by all other statements. Any coherent statement rests on the concepts of existence, identity and consciousness. For example, existence because to say something about something real is to imply that it, the person speaking and any intended listener exists. When discussing things that aren’t real (fiction, fantasy and the like) you are still employing the concept of existence. The very concept of unreal things rests on a contrast to the real. Identity because the words you use are intended to refer to specific concepts and not others. And consciousness because that you are speaking implies that you are aware of the subject and whatever you are predicating of it and that any intended listener will also be aware of the content of your statement.
These three concepts are axiomatic concepts. They are the irreducible and self evident foundation of all other knowledge. They don’t have to be consciously employed or even identified for someone to gain further knowledge, but these concepts do have to be formed and held on some level, be it subconscious and implicit. Any attempt to refute them is self refuting; such an attempt has to imply them while trying to disprove them.
What it means to exist is self evident and requires little explanation. Existence refer to two things; the state of existing and as synonyms with the words universe (when used properly) or reality, the totality of all things that exist. Ayn Rand formulated the formal axiom “Existence exists” meaning, of course, that the totality of all things possess the state of existence. But what is less obvious is that existence is identity. To exist is to be, but to be is to be something. What a thing is is its identity, its nature, the sum of all of its attributes. And to be at all is to have some attributes, a nature, an identity. Existence and identity are the same phenomena looked at from different perspectives; identity is a corollary or existence.
The axiom of identity is classically formulated as “A is A” where A stands for anything. A thing is the thing that it is, it has the attributes that it has, it can do what it can do and only what it can do. All things are limited by their nature. Their attributes allow them only so many possible potentialities. A thing acting against its nature is a thing not being its self. But because a thing is what it is this is impossible, it is a contradiction. A thing cannot be both its self and not its self at the same time and in the same respect. A thing cannot be both A and not A. This is a corollary of the law of identity, this is the law of non-contradiction. This law serves as a link between metaphysics and epistemology. Also implied in all of this is that a thing is either A or not-A. There is no middle between possessing an attribute and not possessing it. To possess an attribute to a lesser degree is still to possess it. This is the law of excluded middle.
Identity applied to actions is the law of causality. Every action is determined by the nature of the entities acting. There can be no such thing as actions apart from entities which act. The way in which a thing acts is necessitated and limited by the kind of thing that it is. There can be no actions without causes. Such would be things acting apart from their nature. An action without a cause is then a contradiction, because it is a thing not being the thing that it is.
“Existence is Identity, Consciousness is Identification.” Consciousness is “the faculty of perceiving that which exists.” To be aware of something requires some form of perception. A tree is not conscious a worm is; a worm can experience sensations. It is aware that something is stimulating its senses. The sensation level alone is the primary level of consciousness, because sensations alone are the primary stuff of awareness. Higher level animals possess the ability to integrate and retain their sensations in the form of percepts. Percepts mean the difference between a hail of disconnected sensations which are forgotten as soon as the stimuli is no longer present and a group of sensations held in awareness and integrated into the awareness of an entity. Because you can form percepts you are aware of a computer screen and not merely a bombardment of unintelligible light waves, though with percepts alone you would not know it as a monitor only as one particular thing apart from other things. We as human beings can condense and integrate our percepts into concepts. We see it as a kind of thing and symbolize that kind of thing with a word. But not for our senses we would not be conscious.
All claims of knowledge must rest on the perception of our senses or they do not have a right to the claim. A mind devoid of content is not a consciousness. Or, as Leonard Peikoff put it, “To be conscious is to be conscious of something.” The only source of such content, our awareness of that “something” is the senses. We can expand our knowledge by isolating attributes of a given entity into abstractions and attributes of those abstractions into further abstractions but we could not reach this kind of mental content without first experiencing the original entity through our senses.
Any attempt to refute the validity of the senses must ultimately rest on
them to be itself valid. But, its validity resting on what it proposes to refute, the truth of such a statement would invalidate the statement. Any “evidence” of the invalidity of the senses must reduce to the senses by the nature of consciousness and thus could not be presented as evidence. This serves to show the axiomatic nature of the validity of the senses.
Because of their place as the foundation of knowledge and the fact of their self evidence the basic philosophical axioms are properly taken as the standard of truth. Anyone that denies them explicitly or by implication is necessarily wrong. To prove something is to show that the subject of a statement exists with the attribute predicated of it as part of its identity. To disprove anything is to show that the predicated attribute is not a part of the subject’s identity.