A long abiding interest of mine has been the convergence of biology with technology. One author who has written extensively about this is Ray Kurzweil. Among the various ways what he refers to as "the singularity” will manifest, is in the wholesale replacement of current biological systems, organ systems, in the human body by non-biological systems. What I found to be one of the more radical examples is the heart. He writes, "as we perfect ways to transfer nanobots to and from the blood supply, we will eventually be able to continuously replace them [replacing] the entire human bloodstream with nonfluid-based delivery of essential nutrients and cells.
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