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John Playfair
(10 Mar 1748 - 20 Jul 1819)
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Science Quotes by John Playfair (12 quotes)
John Playfair
by artist Sir Henry Raeburn (source)
by artist Sir Henry Raeburn (source)
[To] explain the phenomena of the mineral kingdom ... systems are usually reduced to two classes, according as they refer to the origin of terrestrial bodies to FIRE or to WATER; and ... their followers have of late been distinguished by the fanciful names of Vulcanists and Neptunists. To the former of these Dr HUTTON belongs much more than to the latter; though, as he employs the agency both of fire and water in his system, he cannot, in strict propriety, be arranged with either.
— John Playfair
Amid all the revolutions of the globe, the economy of Nature has been uniform, ... and her laws are the only things that have resisted the general movement. The rivers and the rocks, the seas and the continents, have been changed in all their parts; but the laws which direct those changes, and the rules to which they are subject, have remained invariably the same.
— John Playfair
Every river appears to consist of a main trunk, fed from a variety of branches, each running in a valley proportional to its size, and all of them together forming a system of vallies, communicating with one another, and having such a nice adjustment of their declivities that none of them join the principal valley on too high or too low a level; a circumstance which would be infinitely improbable if each of these vallies were not the work of the stream that flows in it.
— John Playfair
It is admitted, on all hands, that the Scriptures are not intended to resolve physical questions, or to explain matters in no way related to the morality of human actions; and if, in consequence of this principle, a considerable latitude of interpretation were not allowed, we should continue at this moment to believe, that the earth is flat; that the sun moves round the earth; and that the circumference of a circle is no more than three times its diameter.
— John Playfair
It was one thing to declare that we had not yet discovered the traces of a beginning, and another to deny that the earth ever had a beginning.
— John Playfair
It was one thing to declare that we had not yet discovered the trace of a beginning, and another to deny that the earth ever had a beginning.
— John Playfair
The Author of nature has not given laws to the universe, which, like the institutions of men, carry in themselves the elements of their own destruction; he has not permitted in his works any symptom of infancy or of old age, or any sign by which we may estimate either their future or their past duration. He may put an end, as he no doubt gave a beginning, to the present system at some determinate period of time; but we may rest assured, that this great catastrophe will not be brought about by the laws now existing, and that it is not indicated by any thing which we perceive.
— John Playfair
The bottom of the sea is the great laboratory, where loose materials are mineralized and formed into stone, the atmosphere is the region where stones are decomposed, and again resolved into earth.
— John Playfair
The powers which tend to preserve, and those which tend to change the condition of the earth's surface, are never in equilibrio; the latter are, in all cases, the most powerful, and, in respect of the former, are like living in comparison of dead forces. Hence the law of decay is one which suffers no exception: The elements of all bodies were once loose and unconnected, and to the same state nature has appointed that they should all return... TIME performs the office of integrating the infinitesimal parts of which this progression is made up; it collects them into one sum, and produces from them an amount greater than any that can be assigned.
— John Playfair
The ridge of the Lammer-muir hills... consists of primary micaceous schistus, and extends from St Abb's head westward... The sea-coast affords a transverse section of this alpine tract at its eastern extremity, and exhibits the change from the primary to the secondary strata... Dr HUTTON wished particularly to examine the latter of these, and on this occasion Sir JAMES HALL and I had the pleasure to accompany him. We sailed in a boat from Dunglass ... We made for a high rocky point or head-land, the SICCAR ... On landing at this point, we found that we actually trode [sic] on the primeval rock... It is here a micaceous schistus, in beds nearly vertical, highly indurated, and stretching from S.E. to N. W. The surface of this rock... has thin covering of red horizontal sandstone laid over it, ... Here, therefore, the immediate contact of the two rocks is not only visible, but is curiously dissected and laid open by the action of the waves... On us who saw these phenomena for the first time, the impression will not easily be forgotten. The palpable evidence presented to us, of one of the most extraordinary and important facts in the natural history of the earth, gave a reality and substance to those theoretical speculations, which, however probable had never till now been directly authenticated by the testimony of the senses... What clearer evidence could we have had of the different formation of these rocks, and of the long interval which separated their formation, had we actually seen them emerging from the bosom of the deep? ... The mind seemed to grow giddy by looking so far into the abyss of time; and while we listened with earnestness and admiration to the philosopher who was now unfolding to us the order and series of these wonderful events, we became sensible how much farther reason may sometimes go than imagination can venture to follow.
— John Playfair
Thus we conclude, that the strata both primary and secondary, both those of ancient and those of more recent origin, have had their materials furnished from the ruins of former continents, from the dissolution of rocks, or the destruction of animal or vegetable bodies, similar, at least in some respects, to those that now occupy the surface of the earth.
— John Playfair
To trace the series of these revolutions, to explain their causes, and thus to connect together all the indications of change that are found in the mineral kingdom, is the proper object of a THEORY OF THE EARTH.
— John Playfair
Quotes by others about John Playfair (1)
How different would geological literature be to-day if men had tried to think and write like Playfair!
See also:
- 10 Mar - short biography, births, deaths and events on date of Playfair's birth.
- John Playfair - Excerpt from Illustrations of the Huttonian Theory of the Earth (1802)