we believe, after a thousand experiments, that a stone will fall, or fire burn; can we ever fatisfy ourselves concerning any determination, which we may form, with regard to the origin of worlds, and the fituation of nature, from, and to eternity?

This narrow limitation, indeed, of our inquiries, is, in every refpect, fo reasonable, that it fuffices to make the flightest examination into the natural powers of the human mind, and to compare them with their objects, in order to recommend it to us. We fhall then find what are the proper fubjects of science and inquiry.

It seems to me, that the only objects of the abstract sciences or of demonstration are quantity and number, and that all attempts to extend this more perfect species of knowledge beyond thefe bounds are mere fophiftry and illufion. As the component parts of quantity and number are entirely fimilar, their relations become intricate and involved; and nothing can be more curious, as well as ufeful, than to trace, by a variety of mediums, their equality or inequality, through their different appearances. But as all other ideas are clearly distinct and different from each other, we can never advance farther, by our utmost scrutiny, than to obferve this diverfity, and, by an obvious reflection, pronounce one thing not to be another. Or if there be any difficulty in these decisions, it proceeds entirely from the undeterminate meaning of words, which is corrected by jufter definitions. That the Square of the hypothenufe is equal to the fquares of the other two fides, cannot be known, let the terms be ever fo exactly defined, without a train of reafoning and inquiry. But to convince us of this propofition, that where there is no property, there can be no injuftice, it is only neceffary to define the terms, and explain injuftice to be a violation of property. This pro

pofition

pofition is, indeed, nothing but a more imperfect definition. It is the fame case with all thofe pretended fyllogiftical reafonings, which may be found in every other branch of learning, except the fciences of quantity and number; and these may fafely, 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 diftinct an idea as its existence. The propofition, which affirms it not to be, however falfe, is no lefs conceivable and intelligible, than that which affirms it to be. The cafe is different with the fciences, properly fo called. Every propofition, which is not true, is there confufed and unintelligible. That the cube root of 64 is equal to the half of 10, is a falfe propofition, and can never be distinctly conceived. But that CAESAR, or the angel GABRIEL, or any being never exifted, may be a falfe propofition, but ftill 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 thefe arguments are founded entirely on experience. If we reafon è priori, any thing may appear able to produce any thing. The falling of a pebble may, for ought we know, extinguish the fun; or the wifh 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 Such is the foundation of mo

that of another *.

* See NOTE [Q]

ral

ral reasoning, which forms the greater part of human knowledge, and is the fource 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 difquifitions in hiftory, chronology, geography, and aftronomy.

The fciences, which treat of general facts, are politics, natural philosophy, phyfic, chymistry, &c. where the qualities, caufes 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 fouls, is compofed partly of reasonings concerning particular, partly concerning general facts. It has a foundation in reafon, fo far as it is fupported by experience. But its best and most solid foundation is faith and divine revelation.

Morals and criticifm are not fo properly objects of the understanding as of taste and fentiment. Beauty, whether moral or natural, is felt, more properly than perceived. Or if we reafon concerning it, and endeavour to fix its standard, we regard a new fact, to wit, the general, taste of mankind, or fome fuch fact, which may be the object of reasoning and inquiry.

When we run over libraries, perfuaded of these principles, what havoc must we make? If we take in our hand any volume; of divinity or school metaphyfics, for inftance; let us afk, Does it contain any abftract reafoning concerning quantity or number? No. Does it contain any experimental reafoning concerning matter of fact and exiftence? No. Commit it then to the flames: For it can contain nothing but sophistry and illufion.

A

DISSERTATION

ON THE

PASSION S.

1.

・SOME

SECT. I.

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

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

2. All good or evil, whence-ever it arifes, produces various paffions and affections, according to the light in which it is furveyed.

When good is certain or very probable, it produces

JOY: