Date: 1696

"Imagine two clocks or watches which agree perfectly ... Put now the soul and the body in place of these two clocks; their accordance may be brought about by one of these three ways."

— Leibniz, Gottfried Wilhelm (1646-1716)

Date: 1714

If we imagine a "machine whose structure makes it think, sense, and have perceptions" enlarged to the size of a mill, upon "inspecting its interior, we will only find parts that push one another, and we will never find anything to explain a perception"

— Leibniz, Gottfried Wilhelm (1646-1716)

Date: 1765

"That is, a sentient or thinking being is not a mechanical thing like a watch or a mill: one cannot conceive of sizes and shapes and motions combining mechanically to produce something which thinks, and senses too, in a mass where [formerly] there was nothing of the kind--something which would li...

— Leibniz, Gottfried Wilhelm (1646-1716)