Question about the 25th amendment

I got a curious question regarding the 25th amendment.

Let’s say the President died of cancer and that the Vice President would have to take over the Presidency. Does he legally required to take over the presidency?

What would happen if he doesn’t?

Section 1 says that the Vice President shall become the President. The word “shall” doesn’t really leave wiggle room, does it?

He could immediately resign, at which point the Speaker of the House would succeed to the office.

But the same Amendment makes it pretty clear that the Prez can resign (as Nixon demonstrated). So while the VP might technically become Prez immediately upon the death of his predecessor, he could also immediately resign, which would basically have the same effect of his not having assumed the office at all.

Since both offices would then be vacant, the Speaker of the House would become Prez.

(or maybe the OP is asking if the VP could refuse the Presidency but remain VP (which would be kind of insane, but anyways)? There I think the answer is pretty clearly no, the VP becomes Prez automatically if his predecessor resigns/dies/is impeached. There’s no wiggle room to allow him to keep his former office).

VP is kind of a cushy job. You get a decent salary, healthcare, armed guards and limos for yourself and your family, and get to go on TV whenever you like.

As long as the president is alive, you are not obligated to do anything except be president of the Senate, which no modern VP ever does except on special occasions. (Remember when a certain candidate for VP suggested he or she would use their position as president of the Senate to reform the Senate? He or she was resoundingly mocked for that.)

I wouldn’t mind being VP for eight years. I think the stress of being President would probably kill me.