Existence unit algebra

Proposition 19.1.11 ([Lurie (2017), Proposition 3.2.1.8]). Let \(\Oo \) be a unital \(\infty \)-operad and let \(C\) be an \(\Oo \)-monoidal \(\infty \)-category. Then the \(\infty \)-category \(\Alg _{\Oo /\Oo }(C)\) of \(\Oo \)-algebras in \(C\) admits an initial object \(\unit _C \in \Alg _{\Oo /\Oo }(C)\). Furthermore, an \(\Oo \)-algebra is initial if and only if the unit maps \(e_x\colon \unit _x \to A_x\) are isomorphisms for all \(x \in \Oo ^{\simeq }\).