Principles Of Human Knowledge - pg. 114

The ideas imprinted on the sense by the Author of Nature are called real things : and those exsited in the imagination being less regular, vivid, and constant, are more properly termed ideas, or images of things, which they copy and represent. But then out sensations, be they never so vivid and distinct, are nevertheless ideas, that is, they exist in the mind, or are perceieved by it, as truly as the ideas of its own framing. The ideas of sense are allowed to have more reality in them, that is, to be more strong, orderly, and coherent than the creatures of the mind ; but this is no argument that they exist without the mind. They are also less dependent on the spirit, or thinking substance which perceives them, in that they are excited by the will of another and more powerful spirit : yet still they are ideas, and certainly no idea, whether faint or strong, can exist otherwise than in a mind perceiving it.