# LXVI explained — Philosophical Works

> Chapter companion for Philosophical Works by René Descartes.

## What happens

Descartes explains that sensations, affections, and appetites can be clearly known if we restrict our judgments to only what is immediately contained in our perception. He notes the difficulty, especially with sensations, because from youth we habitually judge that external things exist exactly as we perceive them, leading to errors.

## Themes in this chapter

### Skepticism and Certainty

The chapter addresses how habitual judgments about sensations lead to uncertainty, and how restricting judgments to immediate perception yields clear knowledge.

### Reason and Method

Descartes prescribes a method for achieving clear knowledge of sensations by excluding external existence from the judgment.

## Character check-ins

### Narrator

The narrator (Descartes) explains the proper method for judging sensations, affections, and appetites.

## Key lines

> There remain our sensations, affections, and appetites, of which we may also have a clear knowledge, if we take care to comprehend in the judgments we form of them only that which is precisely contained in our perception of them, and of which we are immediately conscious.

We can have clear knowledge of our sensations, emotions, and desires if we judge only what is directly present in our perception and immediately known to us.

_Descartes outlines the condition for clear knowledge of internal experiences._

> Thus when, for example, we saw a certain colour, we thought we saw something occupying a place out of us, and which was entirely similar to that idea of colour we were then conscious of; and from the habit of judging in this way, we seemed to see this so clearly and distinctly that we esteemed it ( i.e. , the externality of the colour) certain and indubitable.

For instance, when we see a color, we habitually assume there is something outside us that exactly matches our internal idea of that color, and this habit makes us mistakenly believe the external existence of the color is certain.

_Descartes illustrates how habitual judgment leads to error about the external world._

## Links

- HTML: https://www.betterreads.online/discover/philosophical_works_se/chapters/lxvi
- Book: https://www.betterreads.online/discover/philosophical_works_se
- All chapters: https://www.betterreads.online/discover/philosophical_works_se/chapters