# LIX explained — Philosophical Works

> Chapter companion for Philosophical Works by René Descartes.

## What happens

This chapter explains how universals are formed through the mind's use of a single idea to represent multiple similar individual objects. It describes the five universals—genus, species, difference, property, and accident—using examples such as the number two, triangles, and right-angled triangles to illustrate how these categories arise from comparing and naming shared characteristics.

## Themes in this chapter

### Reason and Method

The chapter demonstrates a methodical approach to understanding how the mind forms universal ideas through comparison and abstraction.

## Character check-ins

### Narrator

The narrator explains the formation of universals and the five common terms.

## Key lines

> Universals arise merely from our making use of one and the same idea in thinking of all individual objects between which there subsists a certain likeness; and when we comprehend all the objects represented by this idea under one name, this term likewise becomes universal.

Universals are created when we apply a single idea to multiple similar objects and then give that idea a common name.

_This defines the origin of universals in the mind's abstraction._

> Finally, if we suppose that of these triangles some are moved and others not, this will be their universal accident; and, accordingly, we commonly reckon five universals, viz. , genus, species, difference, property, accident.

If some triangles are moving and others are not, that is an accidental feature; thus the five universals are genus, species, difference, property, and accident.

_This lists the five categories of universals as traditionally recognized._

## Links

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