heterogeneous as the foul and the body were represented to be. And even when I first entered upon metaphyfical inquiries, I thought that either the material, or immaterial part of the universal fyftem was fuperfluous. But not giving any very particular attention to a fubject on which I could get no light, I relapsed into the general hypothesis of two intirely dif tinct and independent principles in man, connected in fome unknown and incomprehenfible manner; and I acquiefced in it as well as I could.

Father Bofcovich and Mr. Michell's new theory concerning matter, of which I gave an account in my History of Discoveries relating to Vision &c. was calculated, as will be seen, to throw the greatest light on the conftituent principles of human nature; but it was a confiderable time before I could bring myself really to receive a doctrine so new, though so strictly philofophical; and besides I had nothing of a metaphysical nature in contemplation at that time.

It was upon refuming fome of my metaphyfical fpeculations, to which (like most other perfons of a ftudious turn) I had been exceedly attached in the early period of my literary

life (when I published my Examination of the Principles of Common Senfe, as maintained by Dr. Beattie, &c. and when I republished Dr. Hartley's Theory of the Human Mind) that I first entertained a serious doubt of the truth of the vulgar hypothesis; and writing, as I always do, with great frankness, I freely expreffed that doubt, exactly as it then stood in my mind; and I think it is hardly poffible to exprefs any thing with more hesitation and diffidence. The paragraph I allude to is the following:

"I am rather inclined to think, though the

fubject is beyond our comprehenfion at pre"fent, that man does not confift of two princi

ples fo effentially different from one another "as matter and fpirit, which are always defcrib"ed as having no one common property, by "means of which they can affect, or act upon, "each other; the one occupying space, and the "other not only not occupying the least imagi"nable portion of space, but incapable of bear

ing any relation to it; infomuch that, proper"ly speaking, my mind is no more in my bo

dy, than it is in the moon. I rather think that "the whole man is of fome uniform compofition; " and that the property of perception, as well "as the other powers that are termed mental,

"is

“is the refult (whether neceffary, or not) of "fuch an organical structure as that of the "brain: confequently, that the whole man "becomes extinct at death, and that we have "no hope of furviving the grave, but what is "derived from the fcheme of revelation.

I little imagined that fuch a paragraph as this could have given the alarm that I prefently found it had done. My doubts were instantly converted into a full perfuafion, and the cry against me as an unbeliever, and a favourer of atheism, was exceedingly general and loud; and was echoed from quarters where more candour and better difcernment might have been expected. With what intention this was done, is best known to the authors of fuch grofs defamation. Ifhall proceed to relate the confequences of it, for which they are, in fome meafure, answerable.

This odium, which I had thus unexpectedly drawn upon myfelf, ferved to engage my more particular attention to the fubject of it; and this at length terminated in a full conviction, that the doubt I had expreffed was well founded. Continuing to reflect upon the fub- d ject, I became fatisfied that, if we fuffer ourselves to be guided in our inquiries by the univerfally

verfally acknowledged rules of philosophizing, we fhall find ourselves intirely unauthorized to admit any thing in man besides that body which is the object of our senses; and my own obfervations, and my collection of opinions on the fubject, presently fwelled to the bulk that is now before the Public.

Thefe obfervations I now lay before the reader, whatever be his difpofition of mind with respect to myself, or my subject, with the same openness and fimplicity with which I first proposed my fimple doubt; and, judging from what has paffed, I may imagine that, if the fimple doubt occafioned fo great an alarm and outcry, the unreserved avowal of my intire conviction on the subject will cause a much greater alarm. And yet in this apprehenfion I may poffibly be mistaken; and as, on the former occafion, the offence was taken when I was leaft aware of it, the popular clamour may have spent itself, and may begin to fubfide, on the very occafion on which I imagined it would be inflamed to the utmost.

Men of reafon and religion may attend to the arguments that I have produced, from reafon and the feriptures, in fupport of my hypothefis, and may be fatisfied that my opinion is neither

neither irrational in itself, nor deftitute of countenance in the facred writings, and therefore certainly not dangerous; and the favour of the few may filence the clamour of the many.

On the other hand, the tide of popular prejudice may rise still higher, and though I have spent the greatest part of my life in the study and defence of christianity, the suspicion of my being an unbeliever, and an underminer of all religion, may be confirmed; and, like Mr. Hobbes, I may for generations lie under the imputation of abfolute atheism.

Be this as it may; I feel a great present ease in the idea of publishing my thoughts with the moft unreserved freedom on this important fubject; and I am not without hopes that, though many well meaning chriftians may, for fome time, rank me with unbelievers, fome unbelievers, of a philofophical turn of mind, may, on this very account, be prevailed upon to attend to the fubject; and finding the true fyftem of revelation to be quite another thing than they had imagined it to be, and infinitely more confonant to the real appearances of nature, may think it worth their while to confider it in various other lights, and attend to the evidence that myself and others have produced