Was Jean Le Rond d’Alembert largely self-taught in mathematics?

Yes, it is accurate to say that Jean Le Rond d’Alembert was almost entirely self-taught in mathematics.

Although he attended a prestigious Jansenist school where he was initially trained for theology—a subject for which he developed a lifelong aversion—and later studied law and medicine, his formal education did not focus on his primary interest. Aside from receiving a few private lessons, he pursued his mathematical studies independently, eventually dedicating himself to the field because it was the only occupation that truly interested him.1