hard fork(eth: --oppose-dao-fork) = intentional split = mitosis
consensus change = majority upgrade = gene therapy

gene therapy:
if the majority of cells(nodes) accept the new gene(rule), then all cells change to fix a issue to allow the body(network) to healthily grow, without the previous unhealthy limitation.

if the majority of cells(nodes) reject the new gene(rule), then all cells dont change and the body(network) remains having the unhealthy limitation.