cancer is truly nasty thats for sure. some cases can be controlled into remission but its never guaranteed.

my greatest fear is brain deterioration (alzheimers, dementia, things like that) and currently there is no way to prevent, slow down, or cure those.

i can lose large pieces of my body to whatever and as long as my brain is functioning at more or less normal level (for me) im good with missing parts. i can adapt as long as my brain is doing its job in its usual sloppy fashion.

you can replace a lot of organ systems but obviously the brain is not on that list.

i have seen too many people who suffer one or the other of those and how truly miserable that can be to the patient as well as family.

i have a plan to prevent that long spiral downward if my brains craps out. i plan build an extremely complicated puzzle device that takes, say, one hour of undivided attention and and a reasonable amount of logic and such to solve, thereby resetting the counter. it would need to be solved every (say) two weeks, and wrong answers are ignored with no penalty. it would have something like a several month grace period, even with wrong answers. to take into the account other, temporary mental issues. so, basically a dead mans switch that would somehow cause me to expire (with no danger to others) while still having a small shred of dignity and freewill. this would take much careful vetting of course, as well as a way to expire myself (suicide is for cowards, but i figure dying because you could not solve a logic problem is ok... well i think so anyway).

so.. if my brain is going to betray me.. well if i cant trust my own brain at that point, i need to set something up before my brain has a chance to cause a huge amount of suffering and inconvenience for caregivers.