“Electricity, n. The cause of all natural phenomena not known to be caused by something else. It is the same thing as lightning, and its famous attempt to strike Dr. Franklin is one of the most picturesque incidents in that great and good man's career.”

"On Medicine, (c. 1020) http://www.fordham.edu/halsall/source/1020Avicenna-Medicine.html
Context: The knowledge of anything, since all things have causes, is not acquired or complete unless it is known by its causes. Therefore in medicine we ought to know the causes of sickness and health. And because health and sickness and their causes are sometimes manifest, and sometimes hidden and not to be comprehended except by the study of symptoms, we must also study the symptoms of health and disease. Now it is established in the sciences that no knowledge is acquired save through the study of its causes and beginnings, if it has had causes and beginnings; nor completed except by knowledge of its accidents and accompanying essentials. Of these causes there are four kinds: material, efficient, formal, and final.

On the Nature of Places, a continuation of the treatise On Lines, Angles and Figures as quoted by Amelia Carolina Sparavigna, "Translation and discussion of the De Iride, a treatise on optics by Robert Grosseteste" arXiv:1211.5961v1 http://arxiv.org/abs/1211.5961 @arXiv.org, Cornell University (2012)
Context: The diligent investigator of natural phenomena can give the causes of all natural effects... by the rules and roots and foundations given from the power of geometry.

V. On the First Cause
On the Gods and the Cosmos
Context: Next in order comes knowledge of the first cause and the subsequent orders of the Gods, then the nature of the world, the essence of intellect and of soul, then providence, fate, and fortune, then to see virtue and formed from them, and from what possible source evil came into the world.
Each of these subjects needs many long discussions; but there is perhaps no harm in stating them briefly, so that a disciple may not be completely ignorant about them.
It is proper to the first cause to be one — for unity precedes multitude — and to surpass all things in power and goodness. Consequently all things must partake of it. For owing to its power nothing else can hinder it, and owing to its goodness it will not hold itself apart.
If the first cause were soul, all things would possess soul. If it were mind, all things would possess mind. If it were being, all things would partake of being. And seeing this quality in all things, some men have thought that it was being. Now if things simply were, without being good, this argument would be true, but if things that are are because of their goodness, and partake in the good, the first thing must needs be both beyond-being and good. It is strong evidence of this that noble souls despise being for the sake of the good, when they face death for their country or friends or for the sake of virtue. — After this inexpressible power come the orders of the Gods.

End of Ch. 10<!-- quoted in The Advancement of Science, and Its Burdens (1986) by p. 232 -->; the "Congregation of the Index" (the official inquisition censors) declared<!-- on 15 May 1620 --> that the last sentence of this statement was one of eleven passages which should be removed from the work, in this case because it was perceived as implying that God designed things in accord with the Copernican system, rather than that of Ptolemy.
De revolutionibus orbium coelestium (1543)
Context: The forward and backward arcs appear greater in Jupiter than in Saturn and smaller than in Mars, and on the other hand greater in Venus than in Mercury. This reversal in direction appears more frequently in Saturn than in Jupiter, and also more rarely in Mars and Venus than in Mercury. Moreover, when Saturn, Jupiter, and Mars rise at sunset, they are nearer to the earth than when they set in the evening or appear at a later hour. But Mars in particular, when it shines all night, seems to equal Jupiter in size, being distinguished only by its reddish color. Yet in the other configurations it is found barely among the stars of the second magnitude, being recognized by those who track it with assiduous observations. All these phenomena proceed from the same cause, which is the earth's motion.
Yet none of these phenomena appears in the fixed stars. This proves their immense height, which makes even the sphere of the annual motion, or its reflection, vanish from before our eyes. For, every visible object has some measure of distance beyond which it is no longer seen, as is demonstrated in optics. From Saturn, the highest of the planets, to the sphere of the fixed stars there is an additional gap of the largest size. This is shown by the twinkling lights of the stars. By this token in particular they are distinguished from the planets, for there had to be a very great difference between what moves and what does not move. So vast, without any question, is the divine handiwork of the most excellent Almighty.

Sivakozhundu of Tiruvazhundur (1939)

Letter to Benjamin Rush, 4 April 1790. Alexander Biddle, Old Family Letters, Series A (Philadelphia: 1892), p. 55 http://books.google.com/books?id=5d8hAAAAMAAJ&pg=PA55
1790s

Query 28 : Are not all Hypotheses erroneous in which Light is supposed to consist of Pression or Motion propagated through a fluid medium?
Opticks (1704)
Context: To make way for the regular and lasting Motions of the Planets and Comets, it's necessary to empty the Heavens of all Matter, except perhaps some very thin Vapours, Steams or Effluvia, arising from the Atmospheres of the Earth, Planets and Comets, and from such an exceedingly rare Æthereal Medium … A dense Fluid can be of no use for explaining the Phænomena of Nature, the Motions of the Planets and Comets being better explain'd without it. It serves only to disturb and retard the Motions of those great Bodies, and make the frame of Nature languish: And in the Pores of Bodies, it serves only to stop the vibrating Motions of their Parts, wherein their Heat and Activity consists. And as it is of no use, and hinders the Operations of Nature, and makes her languish, so there is no evidence for its Existence, and therefore it ought to be rejected. And if it be rejected, the Hypotheses that Light consists in Pression or Motion propagated through such a Medium, are rejected with it.
And for rejecting such a Medium, we have the authority of those the oldest and most celebrated philosophers of ancient Greece and Phoenicia, who made a vacuum and atoms and the gravity of atoms the first principles of their philosophy, tacitly attributing Gravity to some other Cause than dense Matter. Later Philosophers banish the Consideration of such a Cause out of natural Philosophy, feigning Hypotheses for explaining all things mechanically, and referring other Causes to Metaphysicks: Whereas the main Business of natural Philosophy is to argue from Phenomena without feigning Hypotheses, and to deduce Causes from Effects, till we come to the very first Cause, which certainly is not mechanical.

Homebody (1998)

Letter to a Quaker (1798)
Context: I believe in one God, the first and great cause of all goodness. I also believe in Jesus Christ the redeemer of the world. I also believe in the Holy gost the comforter— here perhaps we may Differ a little as I believe Jesus Christ was from eternity and a part of the godhead — was Detached by the Father to Do a certain piece of service whioh was to take on Human Nature, which Human Nature was to suffer Death for the redemption of Mankind and when that service was compleatly fulfilled that he returned to and was consolidated with the Godhead. I further believe that all that are saved must be saved through the merits of Christ. I believe the Holy gost to be a part of the Divinity of the Father & son coequal with both is left here to comfort all that Hunger & thirst after righteousness a spark of which inhabit the breast of mankind as a monitor. These are apart of my ideas on the subject of religion.