I have received your letter speaking unvaryingly about the changeability of things; by unvaryingly I mean truly, since I consider that which does not vary to be nothing other than truth. Indeed, truth itself is so totally unmoving that the truth even of movement is unmoving. For what is the truth of movement except its own unchanging law that is comprehended in the true definition of truth? Truth is such that it can never be other than itself. Consequently, truth is eternally present and neither passes from the past into the present nor flows from the present into the future. Truth is so present that the truth even of the future and of the past is present. For by that same truth by which it was true from the beginning of time that this or that would at some time be, and by which it is true in the present that this or that is, or was or will be.

Truth is so eternal that even if it is said to have had a beginning at some time, it would certainly have been true before the beginning of time, and it would not have been true except through the same truth, that truth itself would at some time be. And even if truth should be thought ever to cease, then it would be true for all time, yet only through truth itself would it be true, that truth once was. If truth is unmoving in movement, if it is present in past and future, if it is in the beginning without a beginning, if likewise in the end without an end, it is certainly nothing other than the eternal unmoving itself.

The mind therefore, with its natural capacity for truth, partakes of this eternal unmoving. The will, also by its nature longing for truth, can be granted its desire beyond movement and beyond time. Only a life dedicated by choice to the study and cultivation of truth is lived in the fullness of bliss beyond movement and beyond time. Be sure that those who unlawfully and willfully depart from truth, the fount of true happiness, thereupon fall in misery from the bliss of eternity. But those who with all their might draw near to truth, the source of true happiness, at once rise again in bliss to that blessed eternity.

Therefore live happily, as you have begun, in the study and cultivation of truth. For only those live truly and happily who live in truth itself, the fount of true happiness. But only those can ever live in truth itself who always, as far as possible, live for truth.

13 September 1480, Careggi