I wished, by treating Psychology like a natural science, to help her to become one.

In this remark James frames his project as deliberately methodological and reformist: psychology, in his view, was not yet securely established as a “natural science,” but it could be pushed in that direction by adopting the habits of empirical inquiry—careful observation, experimental testing where possible, and disciplined theorizing. The phrasing also signals a transitional moment in late‑19th‑century thought, when psychology was separating from philosophy and aligning itself with physiology and laboratory methods. James’s stance is pragmatic rather than dogmatic: he treats psychology “like” a natural science not because it already fully is one, but because acting as if it were can help create the standards, institutions, and cumulative knowledge that would make it so.