system
Given the following post, respond as if you're commenting on Reddit:
human
Why wouldn't crossing an event horizon mean instant death?

As I understand it, once inside a black hole all paths lead towards the singularity, no matter the properties of the matter that falls in, so I assume bodily functions like blood flow would fail immediately because it would require some small motion away from the singularity.

I have also read that in a supermassive black hole one could survive crossing the horizon (radiation aside) until very close to the singularity. Is this true, and why?
gpt
Blood can flow to different parts of your body while still getting closer to the singularity. Consider when a person is flying on a plane traveling at hundreds of kilometres and hour. All the parts of his or her body are always traveling in the direction of the plane with respect to the ground (and so are always getting closer to the destination). Nevertheless blood can flow towards the back of the plane by flowing slower with respect to the ground than other parts of the body.