“Everything in the Universe was as the Creator willed it — nothing superfluous, nothing lacking — a harmony.”

XII, 30
Meditations (c. 121–180 AD), Book XII
Context: Everything harmonizes with me, which is harmonious to thee, O Universe. Nothing for me is too early or too late, which is in due time for thee. There is one light of the sun, though it is interrupted by walls, mountains and infinite other things. There is one common substance, though it is distributed among countless bodies which have their several qualities. There is one soul, though it is distributed among several natures and individual limitations. There is one intelligent soul, though it seems to be divided.

Pero la vida es corta:
viviendo, todo falta;
muriendo, todo sobra.
Act III, sc. vii. Translation from Arthur Terry Seventeenth-Century Spanish Poetry (Cambridge: CUP, 1993) p. 118.
La Dorotea (1632)

fr. 13
On Nature

"Humanity", Ch.II "Ideologies: A way to live", Part I

Meditations (c. 121–180 AD), Book IV, 23
Original: Πᾶν μοι συναρμόζει ὃ σοὶ εὐάρμοστόν ἐστιν, ὦ κόσμε· οὐδέν μοι πρόωρον οὐδὲ ὄψιμον ὃ σοὶ εὔκαιρον. πᾶν μοι καρπὸς ὃ φέρουσιν αἱ σαὶ ὧραι, ὦ φύσις· ἐκ σοῦ πάντα, ἐν σοὶ πάντα, εἰς σὲ πάντα. ἐκεῖνος μέν φησιν·

introduction to De Curvis Elasticis, Additamentum I to his Methodus Inveniendi Lineas Curvas Maximi Minimive Proprietate Gaudentes 1744; translated on pg10-11, "Leonhard Euler's Elastic Curves" https://www.dropbox.com/s/o09w82abgtftpfr/1933-oldfather.pdf, Oldfather et al 1933
Context: All the greatest mathematicians have long since recognized that the method presented in this book is not only extremely useful in analysis, but that it also contributes greatly to the solution of physical problems. For since the fabric of the universe is most perfect, and is the work of a most wise Creator, nothing whatsoever takes place in the universe in which some relation of maximum and minimum does not appear. Wherefore there is absolutely no doubt that every effect in the universe can be explained as satisfactorily from final causes, by the aid of the method of maxima and minima, as it can from the effective causes themselves. Now there exist on every hand such notable instances of this fact, that, in order to prove its truth, we have no need at all of a number of examples; nay rather one's task should be this, namely, in any field of Natural Science whatsoever to study that quantity which takes on a maximum or a minimum value, an occupation that seems to belong to philosophy rather than to mathematics. Since, therefore, two methods of studying effects in Nature lie open to us, one by means of effective causes, which is commonly called the direct method, the other by means of final causes, the mathematician uses each with equal success. Of course, when the effective causes are too obscure, but the final causes are more readily ascertained, the problem is commonly solved by the indirect method; on the contrary, however, the direct method is employed whenever it is possible to determine the effect from the effective causes. But one ought to make a special effort to see that both ways of approach to the solution of the problem be laid open; for thus not only is one solution greatly strengthened by the other, but, more than that, from the agreement between the two solutions we secure the very highest satisfaction.

Source: The Wild (1995), p. 81