Plutarch De Defectu Oraculorum 3

[3] The company was surprised at this, and Demetrius went so far as to say that it was ridiculous to try in this way to draw great conclusions from small data, not, as Alcaeus ¹ puts it, painting the lion from a single claw, but with a wick and lamp postulating a mutation in the heavens and the universe, and doing away completely with mathematical science.

Neither of these things, said Cleombrotus, will disturb these men; certainly they will not concede any superior accuracy to the mathematicians, since it is more likely that a set period of time, in movements and cycles so far away, should elude mathematical calculation than that the measurement of the oil should elude the very men who were always giving careful attention to the anomaly and watching it closely because of its strangeness. Besides, Demetrius, not to allow that small things are indication of great stands directly in the way of many arts; for it will result in taking away from us the demonstration of many facts and the prognostication of many others. Yet you people try to demonstrate to us also a matter of no small importance: that the heroes of old shaved their bodies with a razor, because you meet with the word razor in Homer ² ; also that they lent money on interest because Homer ³ somewhere says that a debt is owing, not recent nor small, the assumption being that owing signifies accumulating. And again when Homer ⁴ speaks of the night as swift, you cling to the expression with great satisfaction and say that it means this: that the Earth’s shadow is by him called conical, being caused by a spherical body; and as for the idea that medical science can predict a pestilential summer by a multitude of spiders’ webs or by the fig-leaves in the spring when they are like crows’ feet, who of those that insist that small things are not indications of great will allow this to go unchallenged? Who will endure that the magnitude of the sun be measured by reference to a quart or a gill, or that, in the sun-diai here, the inclination of the acute angle which its shadow makes with the level plane be called the measurement of the elevation of the ever-visible pole above the horizon? This was what one might hear from the priests of the prophetic shrine there; so some other rejoinder must be offered to them, if we would make for the sun the wonted order of its course immutable, in accord with the tradition of the ages.

[3] This discourse was much wondered at by the company, and Demetrius amongst the rest affirmed it unreasonable to ground the knowledge of such great matters on such slight and trivial conjectures; for this was not (as Alcacus said) to paint the lion from the measure of his claw, ¹ but to change and disorder the motions of celestial bodies for the sake of a lamp or the snuff of a candle, and to overthrow at one stroke all the mathematical sciences. These men, replied Cleombrotus, will not be moved by what you say; for first, they will not yield to mathematicians in point of certainty, seeing they may be more easily mistaken in their comprehension of time, it being so slippery in its motions and with such distant periods, than these men in the measures of their oil, about which they are so exact and careful because of the strangeness of the thing. Moreover, Demetrius, by denying that small things are oft the signs and indications of great, must prejudice several arts and sciences, and deprive them of the proofs of several conclusions and predictions. And yet you grammarians will needs vouch that the Demi-gods and princes at the Trojan war shaved with razors, because you find in Homer the mention of such an instrument; that also usury was then in fashion, because he says in one place, where you interpret ὀγελλεται to mean increases. And again, when he calls the night quick and sharp, you will needs have him to mean by this word, that the shadow of the earth being round groweth sharp at the end like the body of a cone. Again, who is he that, denying small things to be the signs and proofs of great, will allow what physicians tell us, namely, that we may prognosticate a pestilent summer when great numbers of spiders are seen, and also when the fig leaves in the spring resemble crows’ feet? And who will permit us to measure the greatness of the sun’s body by a pint or gallon of water, or will grant that a small table like a, making a sharp angle leaning on a plane superficies, can show the just measure of the elevation of the pole from the horizon which is ever to be seen in our hemisphere? And this is what the priests may allege in favor of what they affirm; so that we must offer other arguments against them, if we will maintain the course of the sun to be fixed and unchangeable, as we here hold it to be.