434. A man cannot think and will without there being a subject that is a substance out of which and in which he can think and will. Anything that is supposed to come into existence apart from a substantial subject is nothing. This can be known from the fact that a man is unable to see without an organ which is the subject of his sight, or to hear without an organ which is the subject of his hearing. Apart from these organs, sight and hearing are nothing and are not given existence. The same is true of thought, which is an internal sight, and of perception, which is an internal hearing; unless these were in substances and from substances which are organic forms and subjects, they would have no existence at all. From these things it can be confirmed that man's spirit as well as his body is in a form, and that it is in a human form, and enjoys sensories and senses when separated from the body, the same as when it was in it, and that all the life of the eye and all the life of the ear in a word, all the life of sense that man has, belongs not to his body but to his spirit, which dwells in these organs and in their minutest particulars. This is why spirits see, hear, and feel, as well as men. But after being loosed from the body, they do this not in the natural world, but in the spiritual world. The natural sensation that the spirit had, when it was in the body, it had by means of the material part that was added to it; but even then it also felt spiritually in thinking and willing.