Sanity and dementia aren’t so much discrete states as poles of a continuum. It seems to me that slightly irrational (perhaps inappropriate
is a better word) behavior would tend to make other people avoid you. And as you tend to
do less well in social interactions, you would tend to avoid them. Perhaps dementia causes isolation.
Or there’s a positive feedback loop, where increasing dementia causes increasing isolation,
which prompts increasing dementia. . . . One thing is sure, though, a simple correlation
doesn’t prove causation either way.
David Reed Smith
From the Nature Index
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