ONE of the first things to be done in order to the enlargement , and encrease of Knowledg , is to make Men sen●…ible , how imperfect their Vnderstandings are in the present state , and how lyable to deception : For hereby we are disposed to more wari●…ess in our Enquiries , and taken off from ●…old and peremptory Conclusions , which are some of the gre●…test hind●…rances of Intellect●…al improvement●… in the World . Therefore , by way of Intr●…duction to Philosophy and grounded Science , we must endeavour first to destroy the confidence of Assertions , and to establish a prudent reservd●…ss and modesty in Opinions . In order to this , I shall here set down some thoughts I have had on this Subject . And in doing it , I shall

1. Offer some considerable Instan●… of Humane Ignorance and Deficiency , even in the main , and most usual things in Nature . 2. I shall enquire into the Ca●…ses of our imperfection in Knowledg , which will afford further evidence and proof of it : and 3. Add some Strict●…es against Dogmatizing in Philosophy , and all matters of uncertain Speculation .

My Instances shall be drawn , 1. From the Nature of our Souls ; and 2. from the Constitution of our own , and other Bodies .

Ab●… 〈◊〉 former I consider , That if Certainty were any where to be expected , one would think it should be had in the Notices of our Souls , which are our true selves , and whose Sentiments we most in wardly know : In things without us , our shallowness and ignorance need not be matter of much wonder , since we cannot pry into the hidden things of Nature , ●…or obs●…rue the first Springs and Wheels that set the rest in motion . We see but little parcels of the Works of God , and want Phaenomena to make entire and secure Hypotheses : But if that whereby we know other things , know not it self ; If our Souls are strangers to things within them , which they have more advantage to understand than they have in matters of external Nature ; I think then , that this first will be a considerable Instance of the scantness and imperfection of our Knowledg .

( 1. ) I take notice therefore , That the Learned have ever been at great odds and uncertainty about the Nature of the Soul ; concerning which every Philosopher ( almost ) had a distinc●… Opinion : The Chald●…ans held it a Vertue without f●…n ; Xenocrates , and the Aegyptians , a moving N●…ber ; Par●…ider , a compound of Light and Darkness ; Hes●…od and An●…minder , a consistence of Earth and Water : Th●…les call'd in a Nature without rest ; Heraclides supposed it to be Light ; Empedocles to be Blood ; Zeno , the Quintessence of the Elements . G●…len would have it to be an hot Complexion ; Hippocrates , a Spirit diffused through the Body ; Plato , a self-moving Substance ; Aristotle , an Entelechy , or no body knows w●… ; and Var●…o , an heated and dispersed Air.

Thus have some of the greatest Men of ●…ntient times differ'd in one of the first Theories of Humane Nature , which may well be reckon'd an Argument of uncertain●…y and ●…perfection : And yet I account not the difficulties about this , to be so hopeless , as they are in les●… noted Mysteries . The great occasion of this diversity , and these mistakes , is , That Men would form some Image of the Soul in their Fancies , as they do in the contemplation of corporeal Objects ; But this is a wrong way of speculating Immaterials , which may be see●… in their effects and attributes , by way of reflection ; but if , like children we run behind the Glass to look for them , we shall m●… nothing there but disappointment .

2. There hath been as much trouble and diversity in enqui●…ing into the Origine of the Soul , as in se●…hing into the nature of it : In the opinion of some learned M●… , It was from the beginning of the World , created with the Heavens and Light : others have thought it an extract from the Vniversal Soul : Some fancied , it descended from the Moon ; others from the Stars , or vast spaces of the Aether above the Planets , some teach , That God is the immediate Author of it ; some that it was made by Angels ; and some by the Parents . Whether it be Created or Traduced , hath been the great Ball of contention to the latter Ages , and after all the stir about it , 't is still as much a question as ever , and perhaps may so continue till the great Day , that will put an end to all Differences and Disputes . The Patrons of Traduction accuse their Adversaries of affronting the Attributes of God ; and the Assertors of Immediate Creation impeach them of violence to the nature of things : And while each of the Opinions strongly opposeth the other , and feebly defends it self , some take occasion thence to say , That both are right in their Oppositions , but both mistaken in their Assertions . I shall not stir in the Waters that have been troubled with so much contention : The Famous St. Austin , and others of the celebrated Antients , have been content to sit down here in a profest Neutrality , and I will not endeavour to urge Confessions in things that will be acknowledged ; but shall note some Difficulties , that are not so usually observed ; which perhaps have more darkness in them , than these so much controverted Doctrines .

1. I begin with the Vnion of the Soul and Body : In the Vnions that we understand , there is still , either some suitableness and likeness of Nature in the things united , or some middle , participating Being by which they are joyn'd ; but in this there is neither . The natures of Soul and Body , are at the most extream distance ; and their essential Attributes most opposite : To be impenetrable , discerpible and unactive , is the nature of all Body and Matter , as such : And the properties of a Spirit are the direct contrary , to be penetrable , indiscerpible , and self-motive : Yea , so different they are in all things , that they seem to have nothing but Being , and the Transcendental Attributes of that , in common : Nor is there any appearance of likeness between them : For what hath Rarefaction , Condensation , Division , and the other properties and modes of Matter , to do with Apprehension , Judgment , and Discourse , which are the proper acts of a Spiritual Being ? We cannot then perceive any congruity , by which they are united : Nor can there be any middle sort of Nature that partakes of each , ( as 't is in some Unions ) their Attributes being such extreams : or , if there is any such Being , or any such possible , we know nothing of it , and 't is utterly unconceivable . So that , what the Cement should be that unites Heaven and Earth , Light and Darkness , viz. Natures of so diverse a make , and such disagreeing Attributes , is beyond the reach of any of our Faculties : We can as easily conceive how a thought should be united to a Statue , or a Sun-beam to a piece of Clay : how words should be frozen in the Air , ( as some say they are in the remote North ) or how Light should be kept in a Box ; as we can apprehend the manner of this strange Vnion .

2. And we can give no better account how the Soul moves the Body . For whether we conceive it under the notion of a Pure Mind , and Knowledg , with Sir K. Digby ; or of a Thinking Substance , with Des-Cartes ; or of a penetrable , indiscerpible , self-motive Being , with the Platonists ; It will in all these ways be unconceivable how it gives motion to unactive matter : For how that should move a Body , whose nature it is to pass through all Bodies without the least jog or obstruction , would require something more than we know , to help us to conceive . Nor will it avail to say , that it moves the Body by its vehicle of corporeal Spirits ; for still the difficulty will be the same , viz. How it moves them ?

3. We know as little , How the Soul so regularly directs the Animal Spirits , and Instruments of Motion which are in the Body ; as to stir any we have a will to move : For the passages through which the S●…rits are convey'd , being so numerous , and there being so many others that cross and branch from each of them , 't is wonderful they should not lose their way in such a Wilderness : and I think the wit of Man cannot yet tell how they are directed . That they are conducted by some knowing Guide , is evident from the steadiness and regularity of their motion : But what that should be , and how it doth it , we are yet to seek : That all the motions within us are not directed by the meer mechanick frame of our Bodies , is clear from experience , by which we are assured , that those we call Sp●…taneous ones , a●…e under the Government of the Will : at least the determination of the Spirits into such or such passages , is from the Soul , whatever we hold of the con●…eyances after ; and these , I think , all the Philosophy in the World cannot make out to be purely mechanical . But though this be gain'd , that the Soul is the principle of Direction , yet the difficulty is no less than it was before : For unless we allow it a kind of inward sight of every Vein , Muscle , Artery , and other Passage of its own Body ; of the exact site and position of them , with their several Windings , and secret Chanels , it will still be as unconceivable , how it should direct such intricate Motions , as that one that was born blind should manage a Game at Chess , or marshal an Army : And if the Soul have any such knowledg , we are not aware of it ; nor do our minds attend it : Yea , we are so far from this , That many times we observe not any method in the outward performance , even in the greatest variety of interchangable motions , in which a steady Direction is difficult , and a Miscarriage easie : As we see an Artist will play on an Instrument of Musick without minding it ; and the Tongue will nimbly run divisions in a Tune without missing , when the Thoughts are engaged elsewhere : which effects are to be ascribed to some secret Art of the Soul ( if that direct ) to which we are altogether strangers .

4. But besides the Difficulties that lie more deep ; we are at a loss even in the knowledg of our Senses , that seem the most plain and obvious of our Faculties . Our eyes that see other things , see not themselves ; and the Instruments of Knowledg are unknown . That the Soul is the percipient , which alone hath animadversion and sense , properly so call'd ; and that the Body is only the receiver , and conveyer of corporeal Motions , is as certain as Philosophy can make it . Aristotle himself teacheth it in that Maxim , 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 : And Plato affirms , That the Soul hath life and sence ; but that the Body in strictness of speaking , hath neither the one nor other : Upon which position all the Philosophy of Des-Cartes stands : And it is so clear , and so acknowledg'd a Truth , among all considering Men , that I need not stay to prove it : But yet , what are the Instruments of sensitive Perception , and particular convers of outward Motions to the seat of Sense , is difficult to find ; and how the pure Mind can receive information from things that are not like it self , nor the objects they represent , is , I think , not to be explain'd . Whether Sensation be made by corporeal Emissions , and material Images ; or by Motions that are convey'd to the common sense , I shall not dispute : the latter having so generally obtain'd among the Philosophers : But , How the Soul by mutation , and motion in matter , a substance of an other kind , should be excited to action ; and how these should concern it , that is of so divers a nature , is hardly to be conceiv'd . For Body cannot act on any thing , but by Motion ; Motion cannot be receiv'd but by Matter , the Soul is altogether immaterial ; and therefore , how shall we apprehend it to be subject to such Impressions ? and yet Pain , and the unavoidableness of our Sensations evidently prove , That it is subject to them .

Besides , How is it , and by what Art doth the Soul read , That such an Image , or Motion in matter , ( whether that of her Vehicle , or of the Brain , the case is the same ) signifies such an Object ? If there be any such Art , we conceive it not : and 't is strange we should have a Knowledg that we do not know . That by diversity of Motions we should spell out Figures , Distances , Magnitudes , Colours ; things not resembled by them , we must ascribe to some implicit inference , and deduction ; but what it should be ; and by what Mediums that Knowledg is advanced , is altogether unintelligible . For though the Soul may perceive Motions and Images by simple sense , yet it seems unconceivable it should apprehend what they signifie , and represent , but by some secret Art and way of inference : An illiterate Person may see the Letters , as well as the most Learned , but he knows not what they mean ; and an Infant hears the sounds , and sees the motion of the Lips , but hath no conception convey'd to him , for want of knowing the signification of them : such would be our case , not-withstanding all the motions and impressions made by external things , if the Soul had not some unknown way of learning by them the quality of the Objects . For instance , Images and Motions have but very small room in the Brain , where they are receiv'd , and yet they represent the gr●…st Magni●… ; The Image , Figure , ( or what-ev●… else 〈◊〉 may be call'd ) of an Hemisphere of the Heavens , cannot have a Subject larger than the pulp of a Walnut ; and how can such petty Impressions , make known a Body of so vast a wideness , without some kind of Mathematicks in the Soul : And except this be suppos'd , I cannot apprehend how Distances should be perceiv'd ; but all Objects would appear in a cluster . Nor will the Philosophy of Des-Cartes help us here ; For the moving divers Filaments in the Brain , cannot make us perceive such modes as Distances are , unless some such Art and Inference be allow'd , of which we understand nothing .

5. The Memory is a Faculty in us as obscure , and perhaps as un●…ccountable as any thing in Nature . It seems to be an Organical Power , because Diseases do often blot out its Ideas , and cause Oblivion : But what the marks and impr●…ssions are by which the Soul r●…members , is a question that hath not yet been very well res●…'d . There are four principal Hypotheses by which an account hath been attempted ; The Peripatetick , the Cartesian , the Digbaean , and the Hobbian .

1. According to the Peripatetick Schools , Objects are conserv'd in the memory by certain Intentional Species ( as they call them ) a sort of Beings , that have a necessary dependance upon their Subjects ; but are not material in their formal Constitution and Nature . I need not say much against these arbitrary precarious Creatures , that have no foundation in any of our Faculties : Or be that how it will , They are utterly unintelligible ; neither bodily , nor spiritual ; neither produc'd out of any thing , as the matter of their production ; nor out of nothing , which were Creation , and not to be allow'd to be in the power of every , or any finite Being . And though there were no such contradictious contrivance in the framing these Species , yet they could not serve any purpose , as to the Memory , since 't is against the nature of ●…native Effects , such as these are , to subsist but by the continual influence of their Causes ; and so , if this were the true Solution , we could remember nothing longer than the Object was in presence .

2. The account of Des-Cartes is to this purpose ; The Spirits are sent about the Brain , to find the tracks of the Object●… we would call to mind ; which Tracks consist in this , viz , That the Pores through which the Spi●…ts that came from the Objects past , are more easily open'd , and afford a more ready passage to those others that seek to enter ; whence ariseth a special motion in the Glandule , which signifies this to be that we would remember .

But if our Remembrance arise from the easie motion of the Spirits through the opened passages ( according to this Hypothesis ) ? How then do we so distinctly remember such a variety of Objects , whose Images pass the same way ? And how the Distances of Bodies that lie in a Line ? Why should not the impell'd Spirits find other open passages , besides those made by the thing we would remember ? When there are such continual motions through the Brain from numerous other Objects ? Yea , in such a pervious substance as that is , why should not those subtile Bodies meet , every where an easie passage ? It seems to me that one might conceive as well , how every Grain of Corn in a Sieve should be often shaken through the same holes , as how the Spirits in the repeated acts of Memory should still go through the same Pores : Nor can I well apprehend but that those supposed open'd passages , would in a short time be stopt up , either by the natural gravity of the parts , or the making new ones near those ; or other alterations in the Brain .

3. The Hypothesis of Sir Kenelm Digby , is next , viz. That things are preserv'd in the Memory by material Images that flow from them , which having imping'd on the common sense , rebound thence into some vacant Cells of the Brain , where they keep their ranks , and postures , as they entred , till again they are stirr'd , and then they appear to the Fancy as they were first presented .

But how is it conceiveable , That those active Particles which have nothing to unite them , or to keep them in any order , yea which are continually justled by the occursion of other minute Bodies , ( of which there must needs be great store in this Repository ) should so long remain in the same state and posture ? And how is it that when we turn over those Idaea's that are in our memory , to look for any thing we would call to mind , we do not put all the Images into a disorderly floating , and so make a Chaos of confusion there , where the exactest Order is required : And indeed according to this account , I cannot see but that our Memories would be more confused than our Dreams : and I can as easily conceive how an heap of Ants can be kept to regular and uniform Motions .

4. Mr. Hobbs attempts another way ; there is nothing in us , according to this Philosopher , but Matter and Motion : All Sense is Reaction in Matter [ Leviath . Chap. 1. ] the decay of that Motion , and Reaction , is Imagination ; [ Chap. 2. ] And Memory is the same thing , expressing that decay . [ Ib. ] So that according to M. H. all our Perceptions are Motions , and so is Memory : Concerning which , I observe but two things ;

1. Neither the Brain , nor Spirits , nor any other material Substance within the Head , can for any considerable time conserve Motion . The Brain is such a clammy Consistence , that it can no more retain it than a Quagmire ; The Spirits are more liquid than the Air , which receives every Motion , and loseth it as soon : And if there were any other corporeal part in us , as fitly temper'd to keep Motion as could be wisht ; yet ( 2. ) the Motions made in it would be quickly deadned by Counter-Motions ; and so we should never remember any thing , longer than till the next Impression : and it is utterly impossible that so many Motions should orderly succeed one another , as things do in our Memories ; For they must needs , ever and anon , thwart , interfere , and obstruct one another , and so there would be nothing in our Memories , but Confusion and Discord .

Upon the whole we see , that this seemingly plain Faculty , the Memory , is a Riddle also which we have not yet found the way to resolve .

I might now add many other difficulties , concerning the Vnderstanding , Fancy , Will , and Affections : But the Controversies that concern these , are so hotly managed by the divided Sohools , and so voluminously handled by disputing Men , that I shall not need insist on them : The only Difficulties about the Will , its nature and manner of following the Vnderstanding , &c. have confounded those that have enquired into it ; and shewn us little else , but that our Minds are as blind , as that Faculty is said to be by most Philosophers . These Controversies , like some Rivers , the further they run , the more they are hid : And perhaps after all our Speculations and Disputes , we conceive less of them now , than did the more plain , and simple Understandings of former times . But whether we comprehend or not , is not my present business to enquire , since I have confined my self to an Account of some great Mysteries , that do not make such a noise in the World : And having spoken of some that relate to our Souls ; I come now to some others that concern

II. BODIES : I begin with our Own ; which though we see , and feel , and have them nearest to us , yet their inward Constitution and Frame , is hitherto an undiscovered Region : And the saying of the Kingly Prophet , that we are wonderfully made , may well be understood of that admiration , that is the Daughter of Ignorance .