| For as like causes always produce like effects, when in any instance we find our expectation to be disappointed, we must conclude that this irregularity proceeds from some difference in the causes. |
| (7) When any object encreases or diminishes with the encrease or diminution of its cause, it is to be regarded as a compounded effect, derived from the union of the several different effects, which arise from the several different parts of the cause. |
| The absence or presence of one part of the cause is here supposed to be always attended with the absence or presence of a proportionable part of the effect. |
| This constant conjunction sufficiently proves, that the one part is the cause of the other. |
| We must, however, beware not to draw such a conclusion from a few experiments. |
| A certain degree of heat gives pleasure; if you diminish that heat, the pleasure diminishes; but it does not follow, that if you augment it beyond a certain degree, the pleasure will likewise augment; for we find that it degenerates into pain. |
| (8) The eighth and last rule I shall take notice of is, that an object, which exists for any time in its full perfection without any effect, is not the sole cause of that effect, but requires to be assisted by some other principle, which may forward its influence and operation. |
| For as like effects necessarily follow from like causes, and in a contiguous time and place, their separation for a moment shews, that these causes are not compleat ones. |
| Here is all the LOGIC I think proper to employ in my reasoning; and perhaps even this was not very necessary, but might have been supplyd by the natural principles of our understanding. |
| Our scholastic head-pieces and logicians shew no such superiority above the mere vulgar in their reason and ability, as to give us any inclination to imitate them in delivering a long system of rules and precepts to direct our judgment, in philosophy. |
| All the rules of this nature are very easy in their invention, but extremely difficult in their application; and even experimental philosophy, which seems the most natural and simple of any, requires the utmost stretch of human judgment. |
| There is no phaenomenon in nature, but what is compounded and modifyd by so many different circumstances, that in order to arrive at the decisive point, we must carefully separate whatever is superfluous, and enquire by new experiments, if every particular circumstance of the first experiment was essential to it. |
| These new experiments are liable to a discussion of the same kind; so that the utmost constancy is requird to make us persevere in our enquiry, and the utmost sagacity to choose the right way among so many that present themselves. |
| If this be the case even in natural philosophy, how much more in moral, where there is a much greater complication of circumstances, and where those views and sentiments, which are essential to any action of the mind, are so implicit and obscure, that they often escape our strictest attention, and are not only unaccountable in their causes, but even unknown in their existence? I am much afraid lest the small success I meet with in my enquiries will make this observation bear the air of an apology rather than of boasting. |
| If any thing can give me security in this particular, it will be the enlarging of the sphere of my experiments as much as possible; for which reason it may be proper in this place to examine the reasoning faculty of brutes, as well as that of human creatures. |
| SECT. XVI OF THE REASON OF ANIMALS |
| Next to the ridicule of denying an evident truth, is that of taking much pains to defend it; and no truth appears to me more evident, than that beasts are endowd with thought and reason as well as men. |
| The arguments are in this case so obvious, that they never escape the most stupid and ignorant. |
| We are conscious, that we ourselves, in adapting means to ends, are guided by reason and design, and that it is not ignorantly nor casually we perform those actions, which tend to self-preservation, to the obtaining pleasure, and avoiding pain. |
| When therefore we see other creatures, in millions of instances, perform like actions, and direct them to the ends, all our principles of reason and probability carry us with an invincible force to believe the existence of a like cause. |
| It is needless in my opinion to illustrate this argument by the enumeration of particulars. |