out a train of reasoning and inquiry. But to convince us of this proposition, that where there is no property, there can be no injustice, it is only necessary to define the terms, and explain injustice to be a violation of property. This proposition is, indeed, nothing but a more imperfect definition. It is the same case with all those pretended syllogistical reasonings, which may be found in every other branch of learning, except the sciences of quantity and number; and these may safely, I think, be pronounced the only proper objects of knowledge and demonstration.

All other inquiries of men regard only matter of fact and existence; and these are evidently incapable of demonstration. Whatever is may not be. No negation of a fact can involve a contradiction. The non-existence of any being, without exception, is as clear and distinct an idea as its existence. The proposition which affirms it not to be, however false, is no less conceivable and intelligible, than that which affirms it to be. The case is different with the sciences, properly so called. Every proposition, which is not true, is there confused and unintelligible. That the cube root of 64 is equal to the half of 10, is a false proposition, and can never be distinctly conceived. But that Cæsar, or the angel Gabriel, or any being never existed, may be a false proposition, but still is perfectly conceivable, and implies no contradiction.

The existence, therefore, of any being, can only be proved by arguments from its cause or its effect; and these arguments are founded entirely on experience. If we reason a priori, any thing may appear able to produce any thing. The falling of a pebble may, for aught we know, extinguish the sun; or the wish of a man control the planets in their orbits. It is only experience which teaches us the nature and bounds of cause and effect, and enables

us to infer the existence of one object from that of another 2. Such is the foundation of moral reasoning, which forms the greater part of human knowledge, and is the source of all human action and behaviour.

Moral reasonings are either concerning particular or general facts. All deliberations in life regard the former; as also all disquisitions in history, chronology, geography, and astronomy.

The sciences, which treat of general facts, are politics, natural philosophy, physic, chemistry, &c. where the qualities, causes, and effects of a whole species of objects are inquired into.

Divinity or theology, as it proves the existence of a deity, and the immortality of souls, is composed partly of reasonings concerning particular, partly concerning general facts. It has a foundation in reason, so far as it is supported by experience. But its best and most solid foundation is faith and divine revelation.

Morals and criticism are not so properly objects of the understanding as of taste and sentiment. Beauty, whether moral or natural, is felt more properly than perceived. Or if we reason concerning it, and endeavour to fix its standard, we regard a new fact, to wit, the general taste of mankind, or some such fact which may be the object of reasoning and inquiry.

When we run over libraries, persuaded of these principles, what havoc must we make? If we take in our hand any volume; of divinity or school metaphysics, for instance; let us ask, Does it contain any abstract reasoning concerning quantity or number? No. Does it contain any experimental reasoning concerning matter of fact and existence? No. Commit it then to the flames; for it can contain nothing but sophistry and illusion.

a See NOTE [Q.]

DISSERTATION

ON

THE PASSIONS,

1. SOME objects produce immediately an agreeable sensation, by the original structure of our organs, and are thence denominated GOOD; as others, from their immediate disagreeable sensation, acquire the appellation of EVIL. Thus moderate warmth is agreeable and good; excessive heat painful and evil.

Some objects again, by being naturally conformable or contrary to passion, excite an agreeable or painful sensation; and are thence called Good or Evil. The punishment of an adversary, by gratifying revenge, is good; the sickness of a companion, by affecting friendship, is evil.

2. All good or evil, whence-ever it arises, produces various passions and affections, according to the light in which it is surveyed.

When good is certain or very probable, it produces Joy. When evil is in the same situation, there arises GRIEF or SORROW.

When either good or evil is uncertain, it gives rise to

FEAR OF HOPE, according to the degree of uncertainty on one side or the other.

DESIRE arises from good, considered simply; and AVERSION from evil. The WILL exerts itself, when either the presence of the good, or absence of the evil, may be attained by any action of the mind or body.

3. None of these passions seem to contain any thing curious and remarkable, except Hope and Fear, which, being derived from the probability of any good or evil, are mixed passions that merit our attention.

Probability arises from an opposition of contrary chances or causes, by which the mind is not allowed to fix on either side; but is incessantly tossed from one to another, and is determined, one moment to consider an object as existent, and another moment as the contrary. The imagination or understanding, call it which you please, fluctuates between the opposite views; and though perhaps it may be oftener turned to one side than the other, it is impossible for it, by reason of the opposition of causes or chances, to rest on either. The pro and con of the question alternately prevail; and the mind, surveying the objects in their opposite causes, finds such a contrariety as destroys all certainty or established opinion.

Suppose, then, that the object, concerning which we are doubtful, produces either desire or aversion; it is evident, that according as the mind turns itself to one side or the other, it must feel a momentary impression of joy or sorrow. An object, whose existence we desire, gives satisfaction, when we think of those causes which produce it, and for the same reason, excites grief or uneasiness from the opposite consideration. So that, as the understanding, in probable questions, is divided between the contrary points of view, the heart must in the same manner be divided between opposite motions.