I think, I am, I exist - Another writing prompt.

After the deconstruction of the basic foundations (the senses, imagination, and understanding), Descartes makes an argument for the only foundation of sciences: The I-Think.

The argument is structured as a reduction ad absurdum. This means that he starts with an assumption that will lead to a contradiction later, and thus disproves the original assumption.

Descartes starts with the assumption: "I am is a deception." This means that even "I exist" is something that might be a deception by an evil demon.

A deception, however, includes that somebody must be deceived. Even an evil demon is not deceiving nobody. If we take this into account it means that the evil demon deceives somebody of being himself.

This, however, is a contradiction, since the one who is deceived cannot be deceived of being the one who is deceived. If this is, therefore, a contradiction the original assumption must be false and its opposite must be true.

The opposite is: I am not a deception.

From this follows that even the strongest doubt cannot destroy the belief that I am, and thus I am, is an indubitable assumption. This "I am" is in the mode of thinking, since it tries to deny itself by virtue of thoughts. From this follows: I think, I exist.

6 Minutes, 1 minute revised

Proof of my existence (Reductio ad absurdum)

1.  Assumption: The proposition “I am“ is a deception

2. Nevertheless, a deception means that somebody is deceived

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*Therefore: I am deceived of being deceived

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This is a contradiction, since I am the one who is deceived, so I am actually not deceived, I exist

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Final Conclusion: There must be something that is deceived that is me… this is a claim for existence

Argument for Existence

2nd Meditation (Descartes), Specific Argument of Existence, A-Part

Result of 1st Meditation: Knowledge that nothing is certain?

No, because at least: I am I

Proof of my existence (Reductio ad absurdum)

1.  Assumption: The proposition “I am“ is a deception

2. Nevertheless, a deception means that somebody is deceived

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*Therefore: I am deceived of being deceived

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This is a contradiction, since I am the one who is deceived, so I am actually not deceived, I exist

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Final Conclusion: There must be something that is deceived that is me… this is a claim for existence

Descartes, 10 Minute Prompt

Explain what is the content and the method of the Descartesian deconstruction, and explain the three steps of his deconstruction.

The goal of Descartes' Meditation is to give a new foundation to science, because if the foundation is unstable the house of sciences might be in danger. For this goal he uses the method of methodological doubt, this means that he rejects something as false if it has we have the slightest doubt about its truth. At the same time, he wants to find  the foundation as efficiently as possible so that he does not criticize everything. Instead, he systematically attacks the most basic foundations.

The deconstruction follows three steps:

1) He attacks the senses because they seem to be most important for research. The senses, however, just give us knowledge from induction that means they only give us probably knowledge about objects. Since they, however, have deceived us already they cannot be trusted.

Transition: Even though the senses have deceived us, Descartes tries to argue that the images in our head might have been perceived by a transformation. The senses transform a presupposed real object outside of us so that we have an image in our head. If we understand this mechanism, we might be able to infer back to the real object. This is called a metaphysical realism.

2) Descartes rejects also this position, because our images might not have been caused by something outside, but they are the results of our imagination as if we only dream them. So he also rejects this foundation.

Transition to 3: Even though we could be dreaming, dreams, however, must be built on elements. We do not invent all of our dreams. So that these elements could be assumed to be real.

3) Descartes rejects this idea, because these elements could have been put by an evil demon into our mind. So we know them by convention and don't know whether they are really true. Because he has the slightest doubt he also rejects them as a foundation.

8 Minutes.

The Evil-Demon-Argument

Transitioning argument from the senses, and imagination to understanding:

After having demonstrated that we can neither trust the senses, nor our images as representations of real objects, Descartes tries to find another ground for sciences, namely understanding (rationality). So even though we might be trapped in a dream, dreams are composed of elements and these elements are simple. So we can, for example, invent, different objects that are combinations of simple elements, but can we also invent elements?

For example, objects have colors, but can you invent a new color in a dream? Can you invent new shapes?

The following picture resembles an absurd labyrinth, but despite its absurdity it uses elements, in order to be represented in our mind.



So Descartes concludes that the simple elements might qualify as foundations for sciences, but he can also find doubt about this.

The Evil-Demon

So we can believe in the simple elements of understanding. These elements include arithmetic sentences like 2+2=4, geometrical shapes, or even the method of deduction. These statements are evident, but this is not necessarily an indicator that they are true.

The simple task of teaching a child of let us say 4 years the sentence 2+2=4 is much more difficult then we expect. Usually children can count until 4, but they cannot understand what it means to build a some. Numbers are not simple truths, but actually presuppose a complex set of different skills. Because we have trained this sentence for thousands of times, since our early school days, the sentence occurs as evident to us. But could it be that the school has deceived us into believing such simple sentences, so that we believe they are without really knowing this?

The following picture represents this problem. 

So the question of Descartes is legitimate. It could be that an evil teacher, or an evil demon has put these truths in our mind. 

Since Descartes finds the slightest doubt, he dismisses the belief in understanding as a whole.

Further Sources:

• Stories of different demons and paradoxes https://en.wikipedia.org/wiki/Demon_(thought_experiment)
• It is always good to be informed on Realism, a central concept of our time http://plato.stanford.edu/entries/realism/#2
• The wikipedia page gives background information on the evil demon https://en.wikipedia.org/wiki/Evil_demon