Lionel Sharples Penrose, Roger Penrose
Nature 4571, p.1183
ISSN 0028-0836
June 1957
The most striking peculiarity of living organisms is their property of self-reproduction. The most is their property of self-reproduction. The most elementary forms, virus or phage particles, can reproduce themselves in favorable circumstances only, and this principle applies also to the multiplication of nucleic acid complexes in chromosomes. It is sometimes thought that the self-reproducing properties of nucleic acid depend upon its highly complex structure. Consequently, any mechanical analogue for self-reproduction would involve very intricate mechanisms. This does not seem to be so, and the device described here has the critical reproductive property although it is the simplest character.