Our ignorance encompasses, at least, all the things we know we do not
know (known unknowns), all the things we do not know we do not know (u
nknown unknowns); all the things we think we know but do not (error);
all the things we do not know we know (tacit knowing); all taboos (for
bidden knowledge); and all denial (things to painful to know, so we su
ppress them). Medical ignorance seems especially threatening to many o
f us. If, however, we am to cope with our vast ignorance of the human
body, its powers and processes, we must learn to acknowledge our nesci
ence and optimize it. To do so, we need to rethink the nature and inte
rrelations between knowledge and ignorance. We need to expand our capa
cities for self-learning and refine abilities to map our complex exper
ience.