Why did Edmund Husserl criticize naturalism?

Edmund Husserl criticized naturalism because he believed it incorrectly attempted to apply the methods of the natural sciences to all domains of knowledge, including the realm of consciousness.1

Husserl argued that this approach leads to the "naturalization" of reason, which ultimately fails to grasp the true nature of knowledge itself. By relying on experimental psychology to provide a foundation for the human sciences, naturalism overlooks the essential structure of conscious acts.1

For Husserl, philosophy must function as a rigorous science that examines the relationship between consciousness and Being. He maintained that Being is accessible only as a correlate of conscious acts; therefore, the task of phenomenology is to understand the essence of consciousness through immediate, immanent intuition, rather than reducing it to the empirical methods used to study physical facts.1