Meaning of “The cost of a thing is the amount…”

Seneca shifts the complaint from life being too brief to attention and time being poorly spent.

The verse places change inside a larger rhythm of seasons and purposes, making it useful for thinking about acceptance when one phase of life gives way to another.

The emphasis is not on controlling every outcome but on meeting what comes with preparedness and acceptance.

Life continues forward despite attachment to what has already happened, so care for the past cannot make the present remain there.

Mortality cannot be eliminated, so the practical answer is to make conscious use of the finite span between beginning and end.

Time is treated as the substance from which life is built, so wasting it means spending something that cannot be recovered.