The Philosophy of Descartes -- Imagination

Descartes has an Irregular Imagination

I am unjust in blaming the for:

• using the imagination, and
• allowing themselves to be entirely guided by the imagination in their reasonings.

There are two kinds of imagination:

1. The imagination based on permanent, irresistible, and universal principles

Examples are the habitual transition from causes to effects, and from effects to causes.

• These are the foundation of all our thoughts and actions.
• Upon their removal, human nature must immediately perish and go to ruin.

2. The imagination based on changeable, weak, and irregular principles

Examples are those of the ancient philosophers.

• These are avoidable, unnecessary, and not useful.

On the contrary, they:

• only to take place in weak minds,
• are opposite to the other principles of custom and reasoning, and
• may easily be subverted by a due contrast and opposition

This is why philosophy accepts universal principles but rejects the irregular ones. Therefore, the ultimate judge of all systems of philosophy cannot be the irregular kind of imagination.

A person reasons justly and naturally when he concludes that somebody is near him, when he hears a voice, even if that conclusion is only derived from habit.

• This habit infixes and enlivens the idea of a human because of his usual conjunction with the present impression.
• But a person who is tormented by spectres in the dark, might reason naturally too.
  • But then a disease arising from natural causes is also natural, though contrary to health.

The following are like the spectres in the dark:

• the opinions of the ancient philosophers*,
• their fictions of substance and accident, and
• their reasonings on substantial forms and occult qualities.

*Superphysics note: Here, Hume is targetting Aristotle, as seen in Section 3

They are derived from common principles in human nature which are not universal and are avoidable.

The modern philosophy of Descartes pretends to:

• be entirely free from this defect, and
• arise only from the solid, permanent, and consistent principles of the imagination.

Where is this pretension based on?

The fundamental principle of Descartes’ philosophy is its opinion that colours, sounds, tastes, smells, and temperature are nothing but impressions in the mind.

• These impressions are derived from our senses which re-create them in a different way from their true nature in the external objects where they come from.
• Our impressions of the colours, sounds, tastes, smells, and temperature of objects vary even if the external object stays the same.
  • This is the only thing that Descartes gets totally correct

These variations depend on several circumstances:

• on the different situations of our health,
  • A sick man feels a disagreeable taste in meat even if meat pleased him the most before.
• on the different complexions and constitutions of men, and
  • Some seem bitter to one but sweet to another.
• on the difference of their external situation and position.

Colours reflected from the clouds change according to:

• the distance of the clouds, and
• the angle they make with the eye and luminous body.

Fire also communicates the sensation of pleasure at one distance and pain at another.

Examples of this kind are very numerous and frequent. Descartes’ conclusion drawn from them is likewise satisfactory.

But when different impressions of the same sense arise from any object, each of these impressions does not have a resembling quality in the external object.

• That object cannot have different qualities, of the same sense, at the same time.
• The quality of that external object cannot all resemble the different sensory impressions created by our mind about it.

It follows that many of our impressions have no external model or archetype.

From like effects we presume like causes. Many of the impressions of colour, sound, etc. are merely internal existences. The doctrine of Descartes is based on such internal impressions.

• They arise from internal causes in the mind which do not resemble the real causes of those external objects.

These impressions do not appear different from the other impressions of colour, sound, etc.

• But all of them are derived from inside the mind.
• All the other doctrines Descartes’ philosophy follows easily after this principle.