Cellular Senescence: As cells undergo stress, they occasionally become “senescent,” both losing their ability to divide and, simultaneously, becoming resistant to death. These “zombie cells” can’t be removed from the body. They build up over time, infect neighboring cells, and ultimately create a zombie apocalypse of inflammatory debilitation.

I'm getting old, that's the thing! What's in me now won't be there anymore.

When you stop growing you start dying.

You have a finite amount of willpower that becomes depleted as you use it.

Loss of Proteostasis: Inside a cell, proteins run the show. They transport materials, send signals, switch processes on and off, and provide structural support. But proteins become less effective over time, so the body recycles them. Unfortunately, as we age, we can lose this ability. The trash collector goes on strike and we suffer a toxic buildup of proteins that can, for example, lead to diseases such as Alzheimer’s.

You have a finite amount of willpower that becomes depleted as you use it. Your will, in other words, is not a manifestation of your character that you can deploy without limit; it’s instead like a muscle that tires. This is why the subjects in the Hofmann and Baumeister study had such a hard time fighting desires — over time these distractions drained their finite pool of willpower until they could no longer resist. The same will happen to you, regardless of your intentions — unless, that is, you’re smart about your habits.

Every day, without realizing it, we engage in all manner of activities that diminish our willpower. Willpower is depleted when we make decisions to focus our attention, suppress our feelings and impulses, or modify our behavior in pursuit of goals. It’s like taking an ice pick and gouging a hole in our gas line. Before long we have willpower leaking everywhere and none left to do our most important work. So like any other limited but vital resource, willpower must be managed.

When our memories outweigh our dreams, it is then that we become old.

When we can't dream any longer we die.

For passion must, with youth, expire.

You're deep in the nostalgia now,' I told him.

'You get older, you got nothing left,' he said.

brain is just a bunch of cells degrading together because we’re basically just an overclocked ape.

Cuando uno deja de crecer empieza a morir.

He argues that short-term memory pathways will start to deteriorate from underuse if we overuse technology.