Providing Context To
Cogito, ergo sum

A key to understanding René Descartes' most famous line, "I think, therefore I am"

Based upon the notion that we create our own reality And the value of mutual, contradictory realities

17 January 2004

(Original: September 1991)


René Descartes (1596-1650) statement, Cogito, ergo sum, generally translates to “I think, therefore I am.”

For centuries, many people have had issue with this, citing rules of logic being violated or indicating steps were missed. (What comes to mind is The Far Side comic strip with “magic happens” written in the middle of an equation and a fellow suggesting a bit more elaboration there.)

But there is another approach to finding meaning in Descartes' concept.

Understand what he means through the context of perception that defines one’s reality.

My position is that one’s mind creates reality for that person.

Furthermore, the intersection of realities between two or more people is also explored. Mutual, contradictory realities need only be negotiated wherever two people’s realities overlap.

Your Perception Is Your Reality

The concept of existence involves being part of one’s own reality.

We see ourselves as participants within our own life story as it plays out– as opposed to just watching a movie in which someone else was cast. (This uses an assumption common to sociology that might exclude, perhaps, a person born completely paralyzed, deaf and mute). The assumption is that someone is included within his or her own reality.

Perceiving yourself as part of the world in which you live is actually positioning yourself within your reality.

This perceiving occurs through thoughts. As the end of the chain that follows electrical signals flowing through nerves reaching your brain, it is thought that gives meaning to each stimulus from the world around us. This is regardless of whether we are in some tangible, phenomenal world called Earth or jacked into cyberspace as William Gibson penned in Neuromancer and The Wachowskis' movie later portrayed in The Matrix.

As thoughts are the currency of the mind, thinking you are within reality means you are real… to yourself, anyway. This is without defining any ultimate or absolute context. Terms “real” and “reality” are contextual, are relative to one another.

The phrase, “I am,” affirms existence. It’s a claim of being real, of reality.

So the statement, “I think, therefore I am” is an assertion that the one speaking those words exists within their own reality.

This, of course, begs the explanation of contextual reality. More specifically, the plural– contextual realities– must be explained.

Contextual Reality

What is a contextual reality?

The short answer is that each person has his or her own reality, and these realities may both conflict and agree at the same time. The points at which there is conflict or agreement would only be of concern if the two people need interaction which involves those points.

Some reference examples:

Two people, one of which is deaf and the other, blind, each having such traits since birth (and never participated in augmentation treatment such as implantation) obviously perceive totality of the phenomenal world around them differently.

Two people travel from the same neighborhood to the same town center. One rides a bicycle, the other drives a car. As the seasons change, the bicyclist adapts clothing and routes. The other has little reason to dress appropriately for the elements, especially if driving from a garage to another and maintains the belief that the vehicle is unlikely to leave him stranded. Each of these people has a different interaction with the world around them.

Two people of comparable dexterity and physical traits sit in adjacent cubicles of the same office. Both remain at their desks for the duration of the business day, apart from customary breaks and lunch. Both stand at just shy of the cubicle wall height. One desk is next to the window receiving light from the north while the other receives barely any natural light, none of which is direct. Assume all other factors in each of their lives are comparable. Now, let’s set their office in a northern latitude such as Seattle, Iceland or within the Arctic Circle. In these places, dark winters with few hours of daylight mean they arrive at the office in darkness, return home in darkness. These two people perceive differences in quality: the one without the window would probably comment that the winter seems long even when the neighbor does not.

Two brothers– twins– both follow in their family business performing comparable job functions. Both attended the same university, same subjects and both inducted into the same fraternity. One dated the same girl since before college while the other changed partners over the years. Both married within the same year. Later in life, one starts questioning whether he missed out on something while the other, having been with a variety of people while dating, is contented in his marriage.

From the above examples, the common theme is that their perceptions– and hence their realities– are different.

Each pair has different contextual realities.

The deaf and the blind pair would have difficulty communicating about color and sound except on a conceptual level.

The bicyclist and the car driver perceive the same characteristics of weather differently.

The office workers perceive the same passage of time differently. The one tucked away from daylight would have a higher likelihood of developing Seasonal Affective Disorder (SAD), a form of depression common to sufficiently northern areas.

The brothers experienced different relationships and different patterns of dating which contributed to different thought-patterns later in life.

This last example is significant, particularly because it deals with the least tangible. Should the one brother’s thoughts introduce difficulties in his marriage, he might be overheard saying that his world is falling apart. There is a common behavior of drawing upon metaphors of the dissolution of reality when there are drastic changes in one’s life or lifestyle. But beyond rhetoric is a deeper meaning that the perception of his world is now different.

Questions in his mind– thoughts prompting additional thoughts– lead to a transformation of his perceptions, of his reality.

Despite parallels in the lives of the two brothers, they experience different realities through the lens of their respective points of view.

Different thoughts stem from even slightly different courses of action taken.

Different thoughts lead to different perceptions.

Different perceptions of the world around us yields different realities.

It’s the context defined by those perceptions that creates the reality.

As perceptions lead to thoughts which lead to reality, René Descartes' statement of Cogito, ergo sum may be explained as each person experiences their own reality, their own existence.

Thoughts lead to reality– to knowing within oneself– that he or she exists.

But existing in your own reality is different than existing in anyone else’s.

Mutual, Contradictory Realities

To explain mutual, contradictory realities, an example is in order:

Take two people who each live their lives on opposite sides of the planet. They may be unaffected by the other– without getting into subtleties of physics or environmental activism. Their realities may even exclude the other individual without any impact whatsoever.

Take this a step further; another example:

Two people might reside within the same apartment building as neighbors: a man and a woman. She complains to the manager that he plays music too loudly. Meanwhile, he complains of she talking too loud when on the phone or when with visitors. Both claim their own volume levels to be reasonable.

The perspective of each person’s own situation obviously different from the other’s. Their perceptions of the overall situation differs. There is conflict.

That is, their realities are in contradiction despite the overlap of a single, mutually shared apartment building.

Should it turn out that the real issue is deterioration of insulation within the walls, then their perceptions were experiences of artifacts.

Artifacts versus facts– the difference is simply the incorporation of new information into each of their own realities.

Until the matter of the wall came into focus, thought shaped reality. After, thought reshaped reality.

As the rest of their lives were immaterial to the issue at hand, the only aspects that overlapped pertained to noise of the neighbor and being the neighbor of the other’s complaints. That is, these were the components within their shared reality– the only overlap between their individual realities.

To resolve the matter, at some point, the wall became a subject of focus.

They negotiated an additional element into their common, shared reality: the wall between their apartment units.

Once the misunderstand was resolved and the neighbors became friends, their mutually shared realities overlapped ever more.

If, however, the dilapidated wall was never resolved to be the issue and each tenant eventually moved away, any overlap between their realities would then cease. There would be nothing requiring them to negotiate as common between themselves. They’d each have their version of the story without ever again being challenged by the other. In fact, the other need not exist after that. Their realities could then continue to contradict the other.

Miscommunication & Misunderstanding

In general terms, lack of negotiation between multiple mutual, contradictory realities leads to miscommunication and misunderstanding.

Anyone with even minimal life experience can relate to a single word being used by two or more people where each has a slightly different meaning or emphasis applied. This, of course, leads to confusion.

Confusion on behalf of the recipient or listener, when left without being addressed, is misunderstanding.

Confusion unchecked by the provider or speaker, when left without regard for adequate understanding by the other parties, is miscommunication.

Miscommunication and misunderstanding are variations of mutual, contradictory realities.

               *    *   *

An example from computer based virtual reality work provides some clarity regarding mutual, contradictory realities, albeit a much more silly one.

Two VR participants submerge themselves into a single environment.

Alice sees Bob as a clown, and Bob sees Alice with Little People from Celtic mythology scurrying around. Neither Bob sees himself as a clown, however, nor Alice has any indication of there being Little People anywhere.

But none of this matters.

The only important thing is that they recognize the other as Bob and Alice, respectively.

Now let’s say that Bob request a business card from Alice. They must negotiate the following:

  1. The card exists as an object within the shared virtual environment.
  2. The card contains information.
  3. The card is being transferred (or copied) from Alice to Bob.

(By accepting the card, Bob encounters an issue of implicitly trusting information contained, but that is beyond the scope of this document.)

Those three points are the only aspects that matter here in the scope of defining reality or existence.

Nothing else is important, nothing else need be negotiated– considered real– by both of them.

The two people need not even see a representation of the other. It just happens to be useful but still unnecessary.

The computer-based version clarifies certain issues. It forces articulation of thoughts and perceptions. Thoughts become entities within the computer system and perceptions are images projected onto a visual display.

If there’s nothing that needs to be shared, to be mutual between two people’s realities, it need not exist within the computer system or may be omitted from visual display to the other participant.

Using The Alternate Translation

The lesser used translation of “I have thoughts, this is because I exist” may also be supported by arguments presented above.

Rather than “a thought implies a thinker,” it would be more along the lines of the following.

Existence implies a reality, reality is defined by perception, and perception is rooted in thoughts.


What is perhaps the most well known one-liner in philosophy, “I think, therefore I am,” comes to us from Sixteenth Century celebrity, René Descartes.

Meaning may be found by a context or definition of reality.

This requires first understanding reality as a mental construct of the mind, of our own individual perceptions. Each mind creates its own perceptions, its own reality.

Such a notion of reality became popular through the 1990’s especially after mainstream consumption of concepts from computer-based virtual reality:

What we accept as real is actually just results of stimuli fed into our brains and ending that chain is thought.

When discussing more than one person, we must deal with possibilities of mutual, contradictory realities.

Details of each person’s reality may conflict another’s. This is acceptable, except for when particular elements need be shared among those people, among their realities. In such instances, items of commonality need to be negotiated.

Without sufficient negotiation, we find ourselves with things like miscommunication and misunderstanding, a form of mutual, contradictory realities.

These arguments may also be applied to the alternate translation of Descartes' statement, something to the effect of “I have thoughts, this is because I exist.”

It all comes down to context and a broad definition of reality.

Copyright © 1991, 2004 Daniel Joseph Pezely
May be licensed via Creative Commons Attribution.