Kerodon

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Theorem 8.3.3.13 (Yoneda's Lemma for $\infty $-Categories). Let $\operatorname{\mathcal{C}}$ be a locally small $\infty $-category. Then the covariant and contravariant Yoneda embeddings

\[ h_{\bullet }: \operatorname{\mathcal{C}}\rightarrow \operatorname{Fun}( \operatorname{\mathcal{C}}^{\operatorname{op}}, \operatorname{\mathcal{S}}) \quad \quad h^{\bullet }: \operatorname{\mathcal{C}}^{\operatorname{op}} \rightarrow \operatorname{Fun}( \operatorname{\mathcal{C}}, \operatorname{\mathcal{S}}) \]

are fully faithful functors, whose essential images are the full subcategories

\[ \operatorname{Fun}^{\mathrm{rep}}( \operatorname{\mathcal{C}}^{\operatorname{op}}, \operatorname{\mathcal{S}}) \subseteq \operatorname{Fun}( \operatorname{\mathcal{C}}^{\operatorname{op}}, \operatorname{\mathcal{S}}) \quad \quad \operatorname{Fun}^{\mathrm{corep}}(\operatorname{\mathcal{C}}, \operatorname{\mathcal{S}}) \subseteq \operatorname{Fun}( \operatorname{\mathcal{C}}, \operatorname{\mathcal{S}}) \]

spanned by the representable and corepresentable functors, respectively.

Proof. By virtue of Corollary 8.3.2.20, this is a reformulation of Proposition 8.3.3.8. $\square$