DISCUSSION 
with a word and you have to change it to another word of the 
same number of letters without writing down any word which 
makes nonsense. It is a question of a model which would give 
you successive mutations which must be biologically significant. 
Huxley: Lewis Carroll invented that game; he called it 
Doublets. 
Bronowski: You are talking about making an anagram, a 
sensible word, from a set of letters. The thing that we are all 
saying about levels of organization comes to this: natural 
systems work by making anagrams—arranging letters into 
individual syllables, say; then by finding words which can be 
made out of the syllables; and then by making sentences out 
of the words. Once you have thought of that analogy, it is a 
great illumination. 
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