The true method of knowledge is experiment.
Blake presents knowledge as something grounded in experience rather than gained through abstraction alone. In the fuller passage, he links the method of experiment with the human faculty that experiences, suggesting that knowing depends on an active encounter with what is being understood.
In the context of All Religions are One, the statement should not be read simply as an endorsement of the modern scientific method. Blake is developing a broader argument about perception, imagination and the “Poetic Genius”, which he regards as a fundamental human faculty. “Experiment” therefore carries the sense of experience or direct engagement as well as deliberate testing.
The quotation can be applied more generally to learning and inquiry: claims and ideas gain substance when they are examined through experience. Its central concern is epistemological, asking how human beings come to know rather than prescribing a specific scientific procedure.
Full quotation
“As the true method of Knowledge is Experiment, the true faculty of knowing must be the faculty which experiences.”