The Astronomer’s Pretensions: Godwin’s Thoughts on Man

It can scarcely be imputed to me as profane, if I venture to put down a few sceptical doubts on the science of astronomy. All branches of knowledge are to be considered as fair subjects of enquiry: and he that has never doubted, may be said, in the highest and strictest sense of the word, never to have believed…

Now the first rule of sound and sober judgment, in encountering any story, is that, in proportion to the magnitude and seemingly incredible nature of the propositions tendered to our belief, should be the strength and impregnable nature of the evidence by which those propositions are supported.

It is not here, as in matters of religion, that we are called upon by authority from on high to believe in mysteries, in things above our reason, or, as it may be, contrary to our reason. No man pretends to a revelation from heaven of the truths of astronomy. They have been brought to light by the faculties of the human mind, exercised upon such facts and circumstances as our industry has set before us.

To persons not initiated in the rudiments of astronomical science, they rest upon the great and high-​sounding names of Galileo, Kepler, Halley and Newton. But, though these men are eminently entitled to honour and gratitude from their fellow-​mortals, they do not stand altogether on the same footing as Matthew, Mark, Luke and John, by whose pens has been recorded “every word that proceedeth out of the mouth of God.”

The modest enquirer therefore, without pretending to put himself on an equality with these illustrious men, may be forgiven, when he permits himself to suggest a few doubts, and presumes to examine the grounds upon which he is called upon to believe all that is contained in the above passages.

Now the foundations upon which astronomy, as here delivered, is built, are, first, the evidence of our senses, secondly, the calculations of the mathematician, and, in the third place, moral considerations. These have been denominated respectively, practical astronomy, scientific, and theoretical.

As to the first of these, it is impossible for us on this occasion not to recollect what has so often occurred as to have grown into an every-​day observation, of the fallibility of our senses.

It may be doubted however whether this is a just statement. We are not deceived by our senses, but deceived in the inference we make from our sensations. Our sensations respecting what we call the external world, are chiefly those of length, breadth and solidity, hardness and softness, heat and cold, colour, smell, sound and taste. The inference which the generality of mankind make in relation to these sensations is, that there is something out of ourselves corresponding to the impressions we receive; in other words, that the causes of our sensations are like to the sensations themselves. But this is, strictly speaking, an inference; and, if the cause of a sensation is not like the sensation, it cannot precisely be affirmed that our senses deceive us. We know what passes in the theatre of the mind; but we cannot be said absolutely to know any thing, more.

Modern philosophy has taught us, in certain cases, to controvert the position, that the causes of our sensations are like to the sensations themselves. Locke in particular has called the attention of the reasoning part of mankind to the consideration, that heat and cold, sweet and bitter, and odour offensive or otherwise, are perceptions, which imply a percipient being, and cannot exist in inanimate substances. We might with equal propriety ascribe pain to the whip that beats us, or pleasure to the slight alternation of contact in the person or thing that tickles us, as suppose that heat and cold, or taste, or smell are any thing but sensations.

The same philosophers who have called our attention to these remarks, have proceeded to shew that the causes of our sensations of sound and colour have no precise correspondence, do not tally with the sensations we receive. Sound is the result of a percussion of the air. Colour is produced by the reflection of the rays of light; so that the same object, placed in a position, different as to the spectator, but in itself remaining unaltered, will produce in him a sensation of different colours, or shades of colour, now blue, now green, now brown, now black, and so on. This is the doctrine of Newton, as well as of Locke.

It follows that, if there were no percipient being to receive these sensations, there would be no heat or cold, no taste, no smell, no sound, and no colour.

Aware of this difference between our sensations in certain cases and the causes of these sensations, Locke has divided the qualities of substances in the material universe into primary and secondary, the sensations we receive of the primary representing the actual qualities of material substances, but the sensations we receive of what he calls the secondary having no proper resemblance to the causes that produce them.

Now, if we proceed in the spirit of severe analysis to examine the primary qualities of matter, we shall not perhaps find so marked a distinction between those and the secondary, as the statement of Locke would have led us to imagine.

The Optics of Newton were published fourteen years later than Locke’s Essay concerning Human Understanding…

Newton was of opinion that matter was made up, in the last resort, of exceedingly small solid particles, having no pores, or empty spaces within them. Priestley, in his Disquisitions relating to Matter and Spirit, carries the theory one step farther; and, as Newton surrounds his exceedingly small particles with spheres of attraction and repulsion, precluding in all cases their actual contact, Priestley is disposed to regard the centre of these spheres as mathematical points only. If there is no actual contact, then by the very terms no two particles of matter were ever so near to each other, but that they might be brought nearer, if a sufficient force could be applied for that purpose. You had only another sphere of repulsion to conquer; and, as there never is actual contact, the whole world is made up of one sphere of repulsion after another, without the possibility of ever arriving at an end.

“The principles of the Newtonian philosophy,” says our author, “were no sooner known, than it was seen how few in comparison, of the phenomena of nature, were owing to solid matter, and how much to powers, which were only supposed to accompany and surround the solid parts of matter. It has been asserted, and the assertion has never been disproved, that for any thing we know to the contrary, all the solid matter in the solar system might be contained within a nutshell.”

It is then with senses, from the impressions upon which we are impelled to draw such false conclusions, and that present us with images altogether unlike any thing that exists out of ourselves, that we come to observe the phenomena of what we call the universe. The first observation that it is here incumbent on us to make, and which we ought to keep ever at hand, to be applied as occasion may offer, is the well known aphorism of Socrates, that “we know only this, that we know nothing.” We have no compass to guide us through the pathless waters of science; we have no revelation, at least on the subject of astronomy, and of the unnumbered inhabitable worlds that float in the ocean of ether; and we are bound therefore to sail, as the mariners of ancient times sailed, always within sight of land. One of the earliest maxims of ordinary prudence, is that we ought ever to correct the reports of one sense by the assistance of another sense…

There are indeed many objects with which we are conversant, that are in so various ways similar to each other, that, after having carefully examined a few, we are satisfied upon slighter investigation to admit the dimensions and character of others. Thus, having measured with a quadrant the height of a tower, and found on the narrowest search and comparison that the report of my instrument was right, I yield credit to this process in another instance, without being at the trouble to verify its results in any more elaborate method.

The reason why we admit the inference flowing from our examination in the second instance, and so onward, with less scrupulosity and scepticism than in the first, is that there is a strict resemblance and analogy in the two cases. Experience is the basis of our conclusions and our conduct…

But the interval that divides the objects which occur upon and under the earth, and are accessible in all ways to our examination, on the one hand, and the lights which are suspended over our heads in the heavens on the other, is of the broadest and most memorable nature. Human beings, in the infancy of the world, were contented reverently to behold these in their calmness and beauty, perhaps to worship them, and to remark the effects that they produced, or seemed to produce, upon man and the subjects of his industry. But they did not aspire to measure their dimensions, to enquire into their internal frame, or to explain the uses, far removed from our sphere of existence, which they might be intended to serve.

It is however one of the effects of the improvement of our intellect, to enlarge our curiosity. The daringness of human enterprise is one of the prime glories of our nature. It is our boast that we undertake to “measure earth, weigh air, and state the tides.” And, when success crowns the boldness of our aspirations after what vulgar and timorous prudence had pronounced impossible, it is then chiefly that we are seen to participate of an essence divine.

What has not man effected by the boldness of his conceptions and the adventurousness of his spirit? The achievements of human genius have appeared so incredible, till they were thoroughly examined, and slowly established their right to general acceptance, that the great heroes of intellect were universally regarded by their contemporaries as dealers in magic, and implements of the devil. The inventor of the art of printing, that glorious instrument for advancing the march of human improvement, and the discoverer of the more questionable art of making gunpowder, alike suffered under this imputation. We have rendered the seas and the winds instruments of our pleasure, “exhausted the old world, and then discovered a new one,” have drawn down lightning from heaven, and exhibited equal rights and independence to mankind. Still however it is incumbent on us to be no less wary and suspicious than we are bold, and not to imagine, because we have done much, that we are therefore able to effect every thing.

As was stated in the commencement of this Essay, we know our own sensations, and we know little more. Matter, whether in its primary or secondary qualities, is certainly not the sort of thing the vulgar imagine it to be. The illustrious Berkeley has taught many to doubt of its existence altogether; and later theorists have gone farther than this, and endeavoured to shew, that each man, himself while he speaks on the subject, and you and I while we hear, have no conclusive evidence to convince us, that we may not, each of us, for aught we know, be the only thing that exists, an entire universe to ourselves.

We will not however follow these ingenious persons to the startling extreme to which their speculations would lead us. But, without doing so, it will not misbecome us to be cautious, and to reflect what we do, before we take a leap into illimitable space…

It is a memorable and a curious speculation to reflect, upon how slight grounds the doctrine of “thousands and thousands of suns, multiplied without end, and ranged all around us, at immense distances from each other, and attended by ten thousand times ten thousand worlds,” mentioned in the beginning of this Essay, is built. It may be all true. But, true or false, it cannot be without its use to us, carefully to survey the road upon which we are advancing, the pier which human enterprise has dared to throw out into the vast ocean of Cimmerian darkness. We have constructed a pyramid, which throws into unspeakable contempt the vestiges of ancient Egyptian industry: but it stands upon its apex; it trembles with every breeze; and momentarily threatens to overwhelm in its ruins the fearless undertakers that have set it up.

It gives us a mighty and sublime idea of the nature of man, to think with what composure and confidence a succession of persons of the greatest genius have launched themselves in illimitable space, with what invincible industry they have proceeded, wasting the midnight oil, racking their faculties, and almost wearing their organs to dust, in measuring the distance of Sirius and the other fixed stars, the velocity of light, and “the myriads of intelligent beings formed for endless progression in perfection and felicity,” that people the numberless worlds of which they discourse. The illustrious names of Copernicus, Galileo, Gassendi, Kepler, Halley and Newton impress us with awe; and, if the astronomy they have opened before us is a romance, it is at least a romance more seriously and perseveringly handled than any other in the annals of literature.

A vulgar and a plain man would unavoidably ask the astronomers, How came you so familiarly acquainted with the magnitude and qualities of the heavenly bodies, a great portion of which, by your own account, are millions of millions of miles removed from us? But, I believe, it is not the fashion of the present day to start so rude a question. I have just turned over an article on Astronomy in the Encyclopaedia Londinensis, consisting of one hundred and thirty-​three very closely printed quarto pages, and in no corner of this article is any evidence so much as hinted at. Is it not enough? Newton and his compeers have said it.

The whole doctrine of astronomy rests upon trigonometry, a branch of the science of mathematics which teaches us, having two sides and one angle, or two angles and one side, of a triangle given us, to construct the whole…

But the imperfectness of our instruments and means of observation have no small tendency to baffle the ambition of man in these curious investigations…

Such are the difficulties that beset the subject on every side. It is for the impartial and dispassionate observers who have mastered all the subtleties of the science, if such can be found, to determine whether the remedies that have been resorted to to obviate the above inaccuracies and their causes, have fulfilled their end, and are not exposed to similar errors. But it would be vain to expect the persons, who have “scorned delights, and lived laborious days” to possess themselves of the mysteries of astronomy, should be impartial and dispassionate, or be disposed to confess, even to their own minds, that their researches were useless, and their labours ended in nothing.

It is further worthy of our attention, that the instruments with which we measure the distance of the earth from the sun and the planets, are the very instruments which have been pronounced upon as incompetent in measuring the heights of mountains. In the latter case therefore we have substituted a different mode for arriving at the truth, which is supposed to be attended with greater precision: but we have no substitute to which we can resort, to correct the mistakes into which we may fall respecting the heavenly bodies…

Huygens endeavoured to ascertain something on the subject, by making the aperture of a telescope so small, that the sun should appear through it no larger than Sirius, which he found to be only in the proportion of 1 to 27,664 times his diameter, as seen by the naked eye. Hence, supposing Sirius to be a globe of the same magnitude as the sun, it must be 27,664 times as distant from us as the sun, in other words, at a distance so considerable as to equal 345 million diameters of the earth. Every one must feel on how slender a thread this conclusion is suspended.

And yet, from this small postulate, the astronomers proceed to deduce the most astounding conclusions. They tell us, that the distance of the nearest fixed star from the earth is at least 7,600,000,000,000 miles, and of another they name, not less than 38 millions of millions of miles. A cannon-​ball therefore, proceeding at the rate of about twenty miles in a minute would be 760,000 years in passing from us to the nearest fixed star, and 3,800,000 in passing to the second star of which we speak. Huygens accordingly concluded, that it was not impossible, that there might be stars at such inconceivable distances from us, that their light has not yet reached the earth since its creation.

The received system of the universe, founded upon these so called discoveries, is that each of the stars is a sun, having planets and comets revolving round it, as our sun has the earth and other planets revolving round him. It has been found also by the successive observations of astronomers, that a star now and then is totally lost, and that a new star makes its appearance which had never been remarked before: and this they explain into the creation of a new system from time to time by the Almighty author of the universe, and the destruction of an old system worn out with age. We must also remember the power of attraction every where diffused through infinite space, by means of which, as Herschel assures us, in great length of time a nebula, or cluster of stars, may be formed, while the projectile force they received in the beginning may prevent them from all coming together, at least for millions of ages…

Certainly the astronomers are a very fortunate and privileged race of men, who talk to us in this oracular way of “the unseen things of God from the creation of the world,” hanging up their conclusions upon invisible hooks, while the rest of mankind sit listening gravely to their responses, and unreservedly “acknowledging that their science is the most sublime, the most interesting, and the most useful of all the sciences cultivated by man…”

All these questions an untrained and inquisitive mind will ask itself in the propositions of astronomy. We must believe or not, as we think proper or reasonable. We have no way of verifying the propositions by the trial of our senses. There they lie, to be received by us in the construction that first suggests itself to us, or not. They are something like an agreeable imagination or fiction: and a sober observer, in cold blood, will be disposed deliberately to weigh both sides of the question, and to judge whether the probability lies in favour of the actual affirmation of the millions of millions of miles, and the other incredible propositions of the travelling of light, and the rest, which even the most cautious and sceptical of the retainers of modern astronomy, find themselves compelled to receive.

But I shall be told, that the results of our observations of the distances of the heavenly bodies are unvaried. We have measured the distances and other phenomena of the sun, the moon, Mercury, Venus, Mars, Jupiter, Saturn, and their satellites, and they all fall into a grand system, so as to convey to every unprejudiced mind the conviction that this system is the truth itself. If we look at them day after day, and year after year, we see them for ever the same, and performing the same divine harmony. Successive astronomers in different ages and countries have observed the celestial orbs, and swept the heavens, and for ever bring us back the same story of the number, the dimensions, the distances, and the arrangement of the heavenly bodies which form the subject of astronomical science.

This we have seen indeed not to be exactly the case. But, if it were, it would go a very little way towards proving the point it was brought to prove. It would shew that, the sensations and results being similar, the causes of those results must be similar to each other, but it would not shew that the causes were similar to the sensations produced. Thus, in the sensations which belong to taste, smell, sound, colour, and to those of heat and cold, there is all the uniformity which would arise, when the real external causes bore the most exact similitude to the perceptions they generate; and yet it is now universally confessed that tastes, scents, sounds, colours, and heat and cold do not exist out of ourselves. All that we are entitled therefore to conclude as to the magnitudes and distances of the heavenly bodies, is, that the causes of our sensations and perceptions, whatever they are, are not less uniform than the sensations and perceptions themselves…

In reality the observations and the facts of astronomy do not depend either upon the magnitudes or the distances of the heavenly bodies. They proceed in the first place upon what may lie seen with the naked eye. They require an accurate and persevering attention. They may be assisted by telescopes. But they relate only to the sun and the planets. We are bound to ascertain, as nearly as possible, the orbits described by the different bodies in the solar system: but this has still nothing to do, strictly speaking, with their magnitudes or distances. It is required that we should know them in their relations to each other; but it is no preliminary of just, of practical, it might almost be said, of liberal science, that we should know any thing of them absolutely.

The unlimited ambition of the nature of man has discovered itself in nothing more than this, the amazing superstructure which the votaries of contemplation within the last two hundred years have built upon the simple astronomy of the ancients. Having begun to compute the distances of miles by millions, it appears clearly that nothing can arrest the more than eagle-​flight of the human mind. The distance of the nearest fixed star from the earth, we are informed, is at least 7,000,000,000,000 miles, and of another which the astronomers name, not less than 38 millions of millions of miles. The particles of light are said to travel 193,940 miles in every second, which is above a million times swifter than the progress of a cannon-​ball. And Herschel has concluded, that the light issuing from the faintest nebulae he has discovered, must have been at this rate two millions of years in reaching the Earth…