rem id fuisse causa cur pila luderem; nec Hecubam causam interritus fuisse Trojanis, quod Alexandrum genuerit. This passage shows that while the term cause was received, at that time as well as now, in so many vague and uncertain acceptations, Cicero as a philosopher perfectly understood its philosophical import. That is cause, he maintains, which has power to produce the thing called its effect; not merely that which precedes it (as if he had anticipated the theories of Mr. Hume and Dr. Reid) but which efficiently precedes it; as a wound produces death, crudity disease, and fire heat. Here we see that Cicero considers fire the efficient cause of heat. As to the opinion of Newton, that he considered it the business of natural philosophy to investigate efficient causes there cannot be a shadow of doubt. What does he mean when in the commencement of his principia he prescribes his two first rules of philosophising? "No more causes of things are to be admitted than are both true and sufficient to explain the appearances; and for the same appearances, because of the uniformity of nature, the same causes are to be assigned:" What can he here mean by the term cause, true and efficient cause? Take the passages before cited from him, and his opinion is ascertained beyond any dispute. "What the efficient cause (causa efficiens) of attraction is, I do not here inquire. I use the word attraction only in general, to signify the force by which bodies tend towards each other, whatever be the cause of that force." Could he have more distinctly marked the distinction between an efficient cause and the laws by which that cause acts? He evidently regards the efficient cause of attraction as a legitimate object of philosophical research, avowing at the same time that he had not been able to discover it, not being deducible from any phenomena he had witnessed, and he did not choose to frame an hypothesis. Of what nature this efficient cause might have been, in the opinion of this great man, is sufficiently ascertained from the conjecture he modestly

hazards of its being an etherial elastic medium pervading the whole system and binding its parts together.

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Thus, we perceive how fruitless and ineffectual is the attempt of Dr. Reid to enlist Newton of his party. It is true" he says, "that a great deal may be considered as done, when we have discovered some laws of nature, by which a cause acts in producing the phenomena, although that cause itself may remain unknown. In this respect also his views were accurate and profound. Is not much accomplished by him, when from having discovered a few general laws of motion by which bodies gravitate towards each other, he has determined the sizes, distances, periodical revolutions, and all other phenomena of the heavenly bodies, although the occult cause of all these outward appearances remains unrevealed? But could the Grand Agent that produces these results be developed, would not this be making still greater advances towards perfection in the science of physical nature? Wonders have been performed by philosophers in natural science, but still greater wonders might be accomplished, could we once be so fortunate as to attain access to that great Moving Spring that sets into operation the whole vast machinery.

Let us now briefly enter into the merits of Dr. Reid's opinions, and test their own truth without reference to the sentiments of others. On what ground do we conclude that matter is incapable of exerting active power, and that in natural philosophy we have nothing to do with efficient causes. We feel the heat of fire, and perceive the light of the sun. The natural impression of a mind untutored in the language of system is," that fire is," as Cicero says, "the real efficient cause of the heat, and the sun of light." Dr. Reid, however, approaches and informs us that we are all this time mistaken, that it is not the fire which warms us or the sun which gives us light, since matter cannot act; but it is the Creator himself who produces these results by the laws of nature. We stand astonished at the intelligence, and find a

difficulty in comprehending it. It is a mystery too deep to be penetrated except by adepts in the new system of philosophy. If the question were, whether matter possesses in itself the power of originating motion or could become a primary cause, I conceive the case would be entirely altered. We have arguments enough to demonstrate that mind alone could be the originator of motion, and that there must be an immaterial and Intelligent Being, who alone can have been eternal and the Great Cause of all other things. But is there any good ground to infer that it is not in the power of the Almighty, or that this power has not been exercised, to communicate to matter efficacy sufficient to enable it to produce certain results? In fact, have we not incontestible proof that it does produce them? Sir Isaac Newton, we have seen, professed himself unable to ascertain the efficient cause of gravity, and merely conjectures that it may be produced by a thin and elastic fluid; but does he say the same of the rainbow and other optical phenomena? Are not the rays of light the real efficient cause of these beautiful appearances? If we suppose the Supreme Being or mind to be the immediate. cause of light that issues from the sun, is it mind also that is refracted and reflected in drops of rain falling from the clouds, so as to spread upon them, in vision, that variety of colours? There seems to be an evident absurdity in supposing mind to be the only agent throughout the whole chain of causes acting in nature. The heat of the sun between the tropics rarefies the air and occasions the trade-winds; the trade-winds act upon the sails of the vessel so as to propel her in her course; the vessel bears the navigator to his port: Now, it is easy to conceive of the creator as the first link in this chain of causes, and that he communicates to the sun the power to diffuse abroad his heat; but how shall we conceive that it is he himself who acts immediately in rarefying the air, exciting the wind, filling the sails of the vessel, and wafting the navigator to his haven? No doubt all these opera

tions are performed by his appointment and under his superintendance and controul, and all the agents in physical nature, the light, heat, winds, seas, and clouds, when performing the various functions allotted them in creation, are only fulfilling his wise purposes. He has impressed upon all physical principles the laws or rules of their action; but there is a manifest absurdity in supposing him the sole agent in the whole train of events. Is not the wind that fills the sails of the vessel, the efficient cause of its motion in the deep, and the heat that rarefies and excites the air, the efficient cause of the winds? Thousands of other cases might be stated, in which the absurdity of making mind the sole agent in the operations of nature might be displayed; but, we cannot but be of opinion, it would be unnecessary, as those we have already alleged must be sufficient.

The doctrine, therefore, of God's acting by means of instruments or second causes, upon which he has originally impressed their several laws, seems to have a deep foundation in nature and the necessary train of our ideas, and is conformable to the first suggestions of the human mind and the unsophisticated sentiments of all mankind. We construct a complicated piece of machinery, and prepare it for its operations. By the turning of a single wheel we set the whole in motion, one wheel moving a second, and that a third, and so on. Now, although we are ourselves the principal and responsible movers, has not the second wheel the power communicated to it of moving the third, and the third the fourth, and so forth? So it is evidently with God. He made and arranged the vast machinery of the universe, and under his superintendance it is preserved in order, and performs its diversified operations; but does it not exalt our ideas of his wisdom and greatness to suppose, that he has so adjusted its parts to each other, and so exquisitely wrought the whole into a regular system, as that his immediate inter

ference in the scheme, except where he originally contemplated such interference, shall seldom, if ever, be necessary?

There are two particulars in the opinions of Dr. Reid, which it will be worth while to examine a little more minutely; the one, why we should deny to matter the possibility of having active power, even when that power is considered as derived; the other, why we should deny that efficient causes are to be traced in natural events, and yet allow moral agents to be true efficients.

As to the first particular, why we should deny to matter the possibility of possessing active power, even when that power is consi lered as derived, there would seem to be no just ground in nature, or in the connection of our ideas for such an opinion. We have the same reason to believe that material substances possess a power, under the influence of which they act from necessity, as that mind is also endowed with a power, under the influence of which we act voluntarily. The only distinction between them is, that our knowledge and belief of the one is derived from sensation, our knowledge and belief of the other is derived from reflection. From the earliest period of life, we observe the operations of bodies upon one another, and the changes and modifications, which by their applications to each other, they produce. We remark also, when we turn our attention inward and reflect upon the operations of our own minds, that we can fix our attention upon any one subject or change, at pleasure, the train of our thoughts; and moreover, that by the determinations of our will, we can put our bodies into any motion we choose. By sensation, therefore; that is, by observing the actions of bodies. upon each other and the results of those actions, and by reflection also, that is, by observing the operations of our minds and the influence which our wills possess over our bodily ac tions, we arrive at ideas of power, active power, efficiency. Mr. Locke thinks, indeed, and perhaps not without reason, that we have a clearer idea of active power from reflection,