Understanding Perception of Time

We all know that if you live to be eighty, the midpoint of your life is

forty. But you've probably noticed that when you were a kid, a

single day felt like a lifetime. Now that you're older,

days fly by like a rocket. That's because our perception

of time isn't linear, it's logarithmic.

Assuming your first memories start at age four and based on an

average life expectancy of eighty-one years, under a

logarithmic model of time perception, the true midpoint of your

life is exactly eighteen.