Below is an excellent intuitive explanation (in Chinese) of the abstract concept Motif by Grothendieck:

**Brief summary** – **Motif** is the **source** of all “**beautiful things**” expressed in different forms.

Example : God created Natural Numbers (**N**), we express **N** in different forms: Binary (0, 1), Decimal (0, 1, 2 …9), Hexadecimal (0,1, 2…9, a, b, c, …f), etc. However, the “Motif” behind these forms is they all follow : 1) **Commutative** Law ; 2) **Distributive** Law.

Similarly, in **Algebraic Geometry** applying the cohomology from **Algebraic Topology**: étale cohomology, crystalline cohomology, de Rham cohomology are the different forms (~ Binary, Decimal, Hexadecimal), factored throught the common “**Motif**” of the Universal cohomology (~**N**).

**[My Analogy in IT Language**]:

Motif is like Interface or Generic, it spells out only the **specification**, leaving out the **implementation (method)** for actual classes / functions…

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