Observations upon experimental philosophy to which is added The description of a new blazing world / written by the thrice noble, illustrious, and excellent princesse, the Duchess of Newcastle.

25. Of the Motions of Heat and Cold.

THose which affim that Heat and Cold are the two primary and onely causes of the Productions of all natural things, do not consider sufficiently the variety of Nature, but think that Nature produces all by Art; and since Art is found out and practised by Man, Man conceits himself to be above Nature; But as neither Art, nor any particular Creature can be the cause or principle of all the rest, so neither can heat and cold be the prime cause of all natural productions, no more then paint can produce all the parts of a man's face, as the Eyes, Nose, Forehead, Chin, Cheeks,

Lips and the like, or a 〈◊〉〈◊〉 can produce a na∣tural Head, or a suit of Clothes can make the body of Man, for then whensoever the fashioned Garments or Mode-dresses do change, men would of necessity change also; but Art causes gross mistakes and errors, not onely in sensitive, but also in rational perceptions; for sense being deluded, is apt to delude Reason also, especially if Reason be too much indulgent to sense; and therefore those judgments that rely much upon the perception of sense, are rather sensitive then rational judgments; for sense can have but a perception of the exterior figures of objects, and Art can but alter the out∣ward form or figure, but not make or change the in∣terior nature of any thing; which is the reason that artificial alterations cause false, at least uncertain and va∣rious judgments, so that Nature is as various in mens judgments, as in her other works. But concerning heat and cold, my opinion is, that they are like several Colours, some Natural, and some Artificial; of which the Artificial are very inconstant, at least not so lasting as those that are not made by Art; and they which say, that both heat and cold are not made by the sensories or sensitive organs, are in the right, if their mean∣ing be that both heat and cold in their natures and with all their proprieties, as they are particular Creatures, are not made or produced by humane or animal senses; nevertheless the sensitive animal perception of heat and cold is made by the sensitive motions in their sensitive

organs, for what heat and cold soever an animal Crea∣ture feels, the perception of it is made in the sense of touch, or by those sensitive motions in the parts of its body; for as the perception of any other outward ob∣ject is not made by a real entrance of its parts into our sensories, so neither is all perception of heat and cold made by the intermixture of their particles with our flesh, but they are patterned and figured out by the sensitive motions in the exterior parts of the body as well as other objects: I will not say, that cold or heat may not enter and intermix with the parts of some bodies, as fire doth intermix with fuel, or enters into its parts; but my meaning is, that the animal perception of heat and cold is not made this way, that is, by an intermix∣ture of the parts of the Agent with the parts of the Pa∣tient, as the learned call them; that is, of the exterior ob∣ject, and the sentient; or else the perception of all ex∣terior objects would be made by such an intermixture, which is against sense and reason; and therefore even in such a commixture, where the parts of the object enter into the body of the sentient, as fire doth into fuel, the perception of the motions of fire in the fuel, and the fuels consumption or burning, is not made by the fire, but by the fuels own perceptive motions, imitating the motions of the fire; so that fire doth not turn the fuel into ashes, but the fuel doth change by its own corpo∣real figurative motions, and the fire is onely an occa∣sion of it: The same may be said of Cold. Neither is

every Creatures perception alike, no more then it can be said, that one particular Creature, as for example Man, hath but one perception; for the perception of sight and smelling, and so of every sence, are diffe∣rent; nay, one and the same sense may have as many several perceptions as it hath objects, and some sorts of peceptions in some Creatures, are either stronger or weaker then in others; for we may observe, that in one and the same degree of heat or cold, some will have quicker and some slower perceptions then others; for example in the perception of touch, if several men stand about a fire, some will sooner be heated then others; the like for Cold, some will apprehend cold weather sooner then others, the reason is, that in their percep∣tion of Touch, the sensitive motions work quicker or slower in figuring or patterning out heat or cold, then in the perception of others. The same may be said of other objects, where some sentient bodies will be more sensible of some then of others, even in one and the same kind of perception. But if in all perceptions of cold, cold should intermix with the bodies of ani∣mals, or other Creatures, like as several Ingredients, then all bodies upon the perception of cold would dis∣solve their figures, which we see they do not; for al∣though all dissolving motions are knowing and percep∣tive, because every particular motion is a particular knowledg and perception, yet not every perception re∣quires a dissolution or change of its figure: 'Tis true,

some sorts or degrees of exterior heat and cold may oc∣casion some bodies to dissolve their interior figures, and change their particular natures, but they have not power to dissolve or change all natural bodies. Nei∣ther doth heat or cold change those bodies by an inter∣mixture of their own particles with the parts of the bo∣dies, but the parts of the bodies change themselves by way of imitation, like as men put themselves into a mode-fashion, although oftentimes the senses will have fashions of their own, without imitating any other ob∣jects; for not all sorts of perceptions are made by Imi∣tation or patterning, but some are made voluntarily, or by rote; as for example, when some do hear and see such or such things without any outward objects. Where∣fore it is not certain steams, or agitated particles in the air, nor the vapours and effluviums of exterior objects, insinuating themselves into the pores of the sentient, that are the cause of the Perception of Heat and Cold, as some do imagine; for there cannot probably be such differences in the pores of animal Creatures of one sort, as for example of Men, which should cause such a different perception as is found in them; for al∣though exterior heat or cold be the same, yet several animals of the same sort will have several and different perceptions of one and the same degrees of exterior heat and cold, as above mentioned; which difference would not be, if their perception was caused by a real entrance of hot and cold particles into the pores of their bodies:

Besides, Burning-Fevers and Shaking-Agues, prove that such effects can be without such exterior causes. Nei∣ther can all sorts of Heat and Cold be expressed by Wind, Air and Water, in Weather-glasses; for they being made by Art, cannot give a true information of the Generation of all natural heat and cold; but as there is great difference between Natural and Artificial Ice, Snow, Colours, Light, and the like; so be∣tween Artificial and Natural Heat and Cold; and there are so many several sorts of heat and cold, that it is impossible to reduce them all to one certain cause or principle, or confine them to one sort of Motions, as some do believe that all sorts of Heat and Cold are made by motions tending inward and outward, and others, that by ascending and descending, or rising and depressing motions, which is no more probable, then that all Colours are made by the reflexion of Light, and that all White is made by reflecting the beams of light outward, and all black by reflecting them inward; or that a Man when he is on Horse-back, or upon the top of an House, or Steeple, or in a deep Pit or Mine, should be of another figure then of the figure and na∣ture of man, unless he were dissolved by death, which is a total alteration of his figure; for neither Gravity nor Levity of Air, nor Almospherical Pillars, nor a∣ny Weather-glasses, can give us a true information of all natural heat and cold, but the several figurative cor∣poreal motions, which make all things in Nature, do

also make several sorts of heat and cold in several sorts of Creatures. But I observe experimental Philoso∣phers do first cry up several of their artificial Instru∣ments, then make doubts of them, and at last disap∣prove them, so that there is no trust nor truth in them, so much as to be relied on; for it is not an age, since Weather-glasses were held the onely divulgers of heat and cold, or change of weather, and now some do doubt they are not such infallible Informers of those truths; by which it is evident, that Experimental Phi∣losophy has but a brittle, inconstant and uncertain ground, and these artificial Instruments, as Micro∣scopes, Telescopes, and the like, which are now so highly applauded, who knows, but may within a short time have the same fate, and upon a better and more rational enquiry, be found deluders rather then true Informers. The truth is, there's not any thing that has and doth still delude most mens understandings more, then that they do not consider enough the vari∣ety of Natures actions, and do not imploy their reason so much in the search of natures actions, as they do their senses, preferring Art and Experiments before Reason, which makes them stick so close to some par∣ticular opinions, and particular sorts of Motions or Parts, as if there were no more Motions, Parts, or Creatures in Nature, then what they see and find out by their Artificial Experiments.

Thus the variety of Nature is a stumbling-block to

moft men, at which they break their heads of under∣standing, like blind men that run against several posts or walls; and how should it be otherwise, since Na∣tures actions are Infinite, and Mans understanding fi∣nite? for they consider not so much the interior Na∣tures of several Creatures, as their exterior figures and Phonomena's, which makes them write many Para∣doxes, but few Truths, supposing that Sense and Art can onely lead them to the knowledg of truth, when as they delude rather their judgments instead of inform∣ing them. But Nature has placed Sense and Reason together, so that there is no part or particle of Nature which has not its share of reason as well as of sense; for every part having self-motion, hath also knowledg, which is sense and reason, and therefore it is fit we should not onely imploy our senses, but chiefly our reason in the search of the causes of natural effects; for Sense is onely a workman, and Reason is the de∣signer and surveigher, and as reason guides and directs, so ought sense to work. But seeing that in this age, sense is more in fashion then reason, it is no wonder there are so many irregular opinions and judgments a∣mongst men; However, although it be the mode, yet I for my part shall not follow it, but leaving to our Moderns their Experimental or Mode-Philosophy built upon deluding Art, I shall addict my self to the study of Contemplative-Philosophy, and Reason shall be my guide. Not that I despise sense or sensitive

knowledg, but when I speak of sense, I mean the per∣ception of our five exterior senses, helped (or rather deluded) by Art and Artificial instruments; for I see that in this present Age, Learned men are full of Art and Artificial trials, and when they have found out something by them, they presently judg that all na∣tural actions are made the same way; as for example, when they find by Art that Salt will make Snow con∣geal into Ice, they instantly conclude from thence that all natural congelations are made by saline parti∣cles, and that the Primum Frigidum, or the Principal cause of all natural cold must needs be salt, by reason they have found by Art that salt will do the same ef∣fect in the aforesaid commixture with Snow. But how grosly they are deceived, rational men may judg: If I were a Chymist, and acknowledged their com∣mon Principles, I might perchance have some belief in it, but not whilest I follow reason; nay, I perceive that oftentimes our senses are deluded by their own ir∣regularities, in not perceiving always truly and right∣ly the actions of Art, but mistaking them, which is a double error; and therefore that particular sensitive knowledg in man which is built meerly upon artificial experiments, will never make him a good Philoso∣pher, but regular sense and reason must do it, that is, a regular sensitive and rational inquisition into the va∣rious actions of Nature; For put the case a Micro∣scope be true concerning the magnifying of an

exterior object, but yet the magnitude of the object cannot give a true information of its interior parts, and their motions, or else great and large bodies would be interiously known even without Microscopes: The truth is, our exterior senses can go no further then the exterior figures of Creatures, and their exterior acti∣ons, but our reason may pierce deeper, and consider their inherent natures and interior actions; and al∣though it do sometimes erre, (for there can be no perfect or universal knowledg in a finite part con∣cerning the Infinite actions of Nature) yet it may also probably guess at them, and may chance to hit the Truth. Thus Sense and Reason shall be the ground of my Philosophy, and no particular natural effects, nor artificial instruments; and if any one can shew me a bet∣ter and surer ground or Principle then this, I shall most willingly and joyfully embrace it.