“Certain it is, that any supposed obstructions, concerning the quality or temperature of any or every one of those worlds, could not have been any bar in the way of God Almighty, with regard to his replenishing his universal creation with moral agents. The unlimited perfection of God could perfectly well adapt every part of his creation to the design of whatever rank or species of constituted beings, his Godlike wisdom and goodness saw fit to impart existence to; so that as there is no deficiency of absolute perfection in God, it is rationally demonstrative that the immense creation is replenished with rational agents, and that it has been eternally so, and that the display of divine goodness must have been as perfect and complete, in the antecedent, as it is possible to be in the subsequent eternity.”

Source: Reason: The Only Oracle Of Man (1784), Ch. II Section III - Of The Eternity and Infinitude of Divine Providence

Part 2.
Paracelsus (1835)

Source: The Alchemist (1988), p. 151.

Source: Guide for the Perplexed (c. 1190), Part III, Ch.25
Context: It is not unreasonable to assume that the works of God, their existence and preceding non-existence, are the result of His wisdom, but we are unable to understand many of the ways of His Wisdom in His works. On this principle the whole Law of Moses is based; it begins with this principle: "And God saw all that He had made, and behold, it was very good" (Gen. i. 31); and it ends with this principle: "The Rock, perfect is His work" (Deut. xxxii. 4). Note it.

Source: The Sayings and Teachings of the Great Mystics of Islam (2002), p.112

Source: Dictionary of Burning Words of Brilliant Writers (1895), P. 32.

Pt. I, Ch. 2 : The Evanescence of Evil, concluding paragraph
Social Statics (1851)
Context: Man needed one moral constitution to fit him for his original state; he needs another to fit him for his present state; and he has been, is, and will long continue to be, in process of adaptation. And the belief in human perfectibility merely amounts to the belief that, in virtue of this process, man will eventually become completely suited to his mode of life.
Progress, therefore, is not an accident, but a necessity. Instead of civilization being artificial, it is part of nature; all of a piece with the development of the embryo or the unfolding of a flower. The modifications mankind have undergone, and are still undergoing, result from a law underlying the whole organic creation; and provided the human race continues, and the constitution of things remains the same, those modifications must end in completeness.

Book IV, lines 1-2.
The Testament of Beauty (1929-1930)

Memoirs of Aga Khan: World Enough & Time (1954)