Eleventh Lecture
Just think, if human beings did not have the effects of lead within them, without actually having lead in them, they would not be thinking beings. The thought process would continually prove dull due to a latent sclerotization. Knowing this, the process that occurs here, which I have described here, the lead process that counteracts sclerosis, has an illuminating effect on the way in which thinking in human beings comes about in the first place.
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