“Lucretius, the Biochemistry of Olfaction, and Scientific Discovery”
Euphrosyne: Revista de Filologia Clássica
n.s. IX (1978): 7-18
[Reprinted with the permission of the
editorial board of Euphrosyne]
Lucretius, the Biochemistry of Olfaction, and Scientific Discovery
[Page 7] Although the modern world distinguishes between the mechanisms of audition and olfaction, the ancient Roman poet Lucretius1
Titus Lucretius Carus, by general consensus one of the truly great classical Roman poets, is all but unknown to us as an individual. The biographical details are most sketchy, and all we can say with any degree of certainty is that he was born shortly after 100 B. C. and died shortly before 50 B. C. For a very full biographical discussion, see Cyril Bailey, Titi Lucreti Cari De Rerum Natura Libri Sex, volume 1, pp. 1-21 (Oxford 1947).
lumped both, along with voice and taste, among the phenomena explicable on the basis of physical contact between a substrate and an atomic particle. We know today that the mechanics of hearing are not so much a matter of specialized atoms, or molecules, impinging on structures within the ear, but rather of waves of vibrated air doing so. In this little paper I should like to compare the explication of olfaction made by Lucretius and by modern science, and generalize on the results.
There are two passages in the De Rerum Natura which speak directly to our concern:
neu simili penetrare putes primordia forma
415 in naris hominum, cum taetra cadavera torrent,
et cum scena croco Cilici perfusa recens est
araque Panchaeos exhalat propter odores;
(Nor should you imagine that atoms of similar shape work their way into men’s nostrils from the burning of foul corpses, from the fresh sprinkling of Cilician saffron on the stage, and from the Arabian scents that an altar gives off.)2
All Latin citations are by book and line numbers from the Oxford Classical Text of Cyril Bailey, Lucreti De Rerum Natura Libri Sex, 2nd edition (Oxford 1959). The translations are my own, and pretend only at exactness, not literary merit; words within parentheses in the body of the translations are my clarifying expansions of the Latin.
[page 8] IV.673-705:
Nunc age, quo pacto naris adiectus odoris
tangat agam. primum res multas esse necessest
675 unde fluens volvat varius se fluctus odorum,
et fluere et mitti volgo spargique putandumst;
verum aliis alius magis est animantibus aptus,
dissimilis propter formas. ideoque per auras
mellis apes quamvis longe ducuntur odore,
680 vulturiique cadaveribus; tum fissa ferarum
ungula quo tulerit gressum promissa canum vis
ducit, et humanum longe praesentit odorem
Romulidarum arcis servator, candidus anser.
sic aliis alius nidor datus ad sua quemque
685 pabula ducit et a taetro resilire veneno
cogit, eoque modo servantur saecla ferarum.
Hic odor ipse igitur, naris quicumque lacessit,
est alio ut possit permitti longius alter;
sed tamen haud quisquam tam longe fertur eorum
690 quam sonitus, quam vox, mitto iam dicere quam res
quae feriunt oculorum acies visumque lacessunt.
errabundus enim tarde venit ac perit ante
paulatim facilis distractus in aeris auras;
ex alto primum quia vix emittitur ex re;
695 nam penitus fluere atque recedere rebus odores
significat quod fracta magis redolere videntur
omnia, quod contrita, quod igni conlabefacta.
deinde videre licet maioribus esse creatum
principiis quam vox, quoniam per saxea saepta
700 non penetrat, qua vox vulgo sonitusque feruntur.
quare etiam quod olet non tam facile esse videbis
investigare in qua sit regione locatum;
refrigescit enim cunctando plaga per auras
nec calida ad sensum decurrunt nuntia rerum.
705 errant saepe canes itaque et vestigia quaerunt.
[But let me now get on with my explanation of how the application of a smell to the nose affects it. First there have to be many objects from which the varied and flowing flood of smells is set rolling (675); this flood should be conceived of as flowing, being emitted and scattered in every direction. Moreover, smells are differentially better suited to different animals because (the smells have) unlike shapes. That is the reason why bees are attracted over enormous distances by the scent of honey, or vultures, by that of corpses (680). And strong dogs, moreover, who have been sent on ahead, lead (their masters on) to the spots where cloven-hoofed beasts have gone; the white goose that saved the citadel of early Rome noted from afar the scent of men (who came to destroy Rome). In such a way different animals endowed with their different smells are attracted each to its own food, and, compelled to reject what is a foul poison (685), preserves the generation of beasts. [page 9] Although this very smell which excites the nose has varying capacities for distance of movement through (space), never is any smell carried so far as sound, or voices, not to mention those things (690) which strike the eyeballs and excite vision. For smell, in its meandering way, arrives slowly and even undergoes gradual destruction as it is easily dissipated into the wafting winds. The reason for this is, first, that smell barely emanates from a thing, (coming as it does) from deep within: that smells do flow into things and flow back from them from deep within (695) is indicated by the fact that objects seem to smell more when they are broken, crushed or destroyed in fire; in the second place, one can see that smell is made up of larger basic units than voice, since smell does not pierce stone enclosures where voice and sound commonly go (700). As a consequence you will see that it is not easy to investigate the exact location of that which has smell. For the impact (of smells) gets cold on its dilatory (journey) through the air, and (these) announcers of objects come to the senses cooled. And so, too, often dogs lose their way and (must) seek out the spoor.]
The salient points of Lucretius’ atomic theory may conveniently be recollected at this point, for only from an understanding of his conception of atoms can we appreciate the implicit mechanisms that underlie his description of olfaction. His physics is classical in its insistence on the conservation of matter, and essentially anti-theological in its denial of divine causality.
In Book I of the De Rerum Natura the fundamental physical principles are outlined: 1) nothing is ever created out of nothing by diving fiat (150: nullam rem e nilo gigni divinitus umquam); 2) nature breaks things back down into its “bodies” and does not destroy things into nothing (215: … quidque in sua corpora rursum/dissolvat natura neque ad nilum interimat res); 3) and nature functions by means of those invisible bodies (328: corporibus caecis igitur natura gerit res) as 4) they move through the vastness of empty space, his fourth and necessary principle (334-6: quapropter locus est intactus inane vacansque./quod si non esset, nulla ratione moveri/res possent …).
More immediately pertinent to the present inquiry is the fairly detailed description of the characteristics and shapes of those corpora, or primordia, which may variously be translated as bodies, first-beginnings, or atoms or molecules3. The bulk of the poem’s Second Book is given over to this matter. [page10]
Lucretius does not distinguish clearly between atoms and molecules, as modern chemistry must, nor, quite obviously, does he ever move to the sub-atomic level. But there is a very definite awareness in his system of the existence of “mixes” in the visible world:
nil esse, in promptu quorum natura videtur,
quod genere ex uno consistat principiorum
nec quickquam quod non permixto semine constet;
(no thing which is visible exists that consists of a single type of first-beginnings, nor any thing which does not consists of mingled seed).
Bodies are themselves endowed with characteristics4
See De Rerum Natura, 1. 483ff.; 1. 449ff.
that are of great importance in the explanation of nature’s working. Aside from their eternal and constant movement (II.121f.: primordia rerum/ … in mango iactari semper inani), they have shape, which is the feature most critical to our purposes.
The various external configurations of “bodies” and the effects consequent on such shapes are explained in the central section of Book Two (333-729). Although atoms are infinite in number, they are not infinite in the number of shapes which they assume. And it is precisely because of their differences in shape and size that the atoms give rise to varied phenomena and physical objects, and, of course, to different sensations, such as one smell from saffron and another from burning corpses. Basic to the notion of atomic figura (shape, or external configuration) in Lucretius’ explanation of the universe is the concept of smoothness and hookedness: the fundamental particles are smooth and round (II.402: levibus atque rotundis), and hooked (II.405: hamatis) and branched (II.446: ramosis). But there is, as one might expect, a third category which seems to fall somewhere between the extremes:
sunt etiam quae iam nec levia iure putantur
esse neque omnino flexis mucronibus unca,
sed magis angellis paulum prostantibus, utqui
titillare magis sensus quam laedere possint,
430 fecula iam quo de genere est inulaeque sapores.
[There are also those particles which cannot legitimately be considered to be either smooth or hooked (and equipped) with bent edges; but (they consist), instead, of small angles that jut out just a bit in such a way that the particles can rather excite the senses than harm them, as for example in the case of wine lees or the flavor of endive.]
Lucretius accounts for the variability of atomic shapes from the hypothetical existence of minimae partes, or smallest constituents (II.485ff.). The atoms, or particles, are the smallest units, but these units are themselves thought of as made up of entities (i.e. the minimae partes) which cannot exist independently, but only as parts of the atoms. And these minimae partes are limited in number, since otherwise continuing additions of minimae partes would render an atom too large. Hence the limit on shape that atoms can assume.
Certain analogies to modern chemistry immediately occur. In his insistence on the variability of physical properties as a function of atomic configuration, Lucretius is astonishingly close to modern explanations for such [page 11] observable facts as melting point, boiling point, and other physical properties, all functions of molecular isomerism. The aliphatic hydrocarbons, for example, such as the pentanes or pentenes, each group having identical molecular weights, differ remarkably in physical properties – a difference which modern structural chemistry accounts for quite elegantly on the basis of isomerism, and specifically what is today referred to as “branching” chains. A “branched” isomer will, quite literally, be more closely entwined with its neighboring molecule than its close cousin, the “straight” isomer, and therefore will require more energy to break free of its environment. And this in effect raises its evaporation point, as an instance.
An analogy can also be drawn between the Lucretian concept of minimae partes of atoms and the modern theory of macromolecular agglutination. It is a known fact of protein chemistry, for example, that relatively few different atoms (mainly carbon, hydrogen, oxygen and nitrogen; some sulphur and phosphorus; traces of some other elements such as iron, iodine, etc.) enter into the make-up of the hundreds or possibly thousands of copies of each amino acid that belongs in a given protein molecule. A sort of tertiary hierarchy exists, then, of atoms, amino acids and protein molecule. Similarly Lucretius is hypothecating the existence of minimae partes as constituents of his basic particles which, in turn, make-up in their multitudinous combinations the many physical objects of the universe (II.581-99, 661-99). And the minimae partes can no more exist independently of Lucretius’ atoms than the atoms of modern chemistry (even, apparently, among the so-called inert family) can exist independent of their ionic-crystal lattices or co-valent bonding.
I shall return later to these matters of Lucretius and modern chemistry. Now that we have considered the fundamentals of Lucretius’ atomic theory, as well as his account (cf. the long passage at the beginning of this paper) of the sensory phenomenon of olfaction, it is time to look at the modern theories of olfaction.
Work by Amoore and others has shown quite conclusively that the sense of smell in humans and animals (frogs and bees) depends on the stereotaxic characteristics of given molecules5.
“The Stereochemical Theory of Odor”, reprint 297 from Scientific American (February 1964), pp. 7ff.
Research indicates that the detection of odors takes place through specifically shaped receptor sites in the olfactory bulb (of humans) or (as in the case of bees) on the antennae.
The theory is a specific instance of the now common generalization in modern biochemistry about lock-and-key. This theory of “fit” has proved very useful as a descriptive model of a number of basic biochemical processes, such as enzymatic catalysis: a given protein (i.e. enzyme) displays rigid molecular [page 12] stereospecifity in that it operates only on a very specific substrate or, even (when ligated to so-called allosteric regulators) only a restricted surface area of the full substrate molecule6;
A. L. Lehninger, Biochemistry (New York 1970), pp. 169f. On the complex matter of allosterism and biofeedback at the molecular level, see Robert C. Bohinski, Modern Concepts in Biochemistry (Boston 1973), pp. 124-138.
or nucleic acid chemistry, where the theory of antiparallel complementarity of stereospecific bases accounts with such intellectually satisfying economy for the double-helical structure of deoxyribonucleic acids (DNA)7.
White-Handler-Smith, Principles of Biochemistry, 5th edition (1973), pp. 188-194.
So, too, this useful generalization has application for a theory of olfaction, which may be seen as a further corroboration of this basic concept in modern biochemistry8.
G. E. W. Wolstenholme and Julie Knight (editors), Taste and Smell in Vertebrates (London 1970), p. 299. And see the very recent and stimulating paper by Donald J. and Jane M. Cram, “Host-Guest Chemistry”, Science 183. 4127 (1st March 1974), pp. 803-809.
In addition to the stereotaxic approach to an understanding of olfaction, however, recent investigations by Steiner have shown that electrophysiological properties of a given odorant molecule are as important as (and a result of) its strictly steric configuration9.
Walter Steiner, “Geruch und Geruchlosigkeit – eine Folge der sterischen und elektrischen Moleküleigenschaften”, Journal of the Society of Cosmetic Chemists 20 (1969), pp. 724-41. See especially p. 233: “Der charakteristische Molekülbau hat zur Folge, dass die Riechstoffmoleküle ein permanents Dipolmoment aufweisen und in der Regel zusätzlich durch die tertiären und quartären C-Atome und durch Doppelbindungen polarisierbar sind.”
I shall return to this point shortly in discussing Lucretius’ notions about foramina, or pores, and the modern theory of electric potentials induced by molecules of given shapes at the water-lipid interface of cellular membranes.
Work by Amoore on the correlation between molecular shape and odor has been carried out. By use of X-ray diffraction analysis and computer assessment of scans it has been possible to establish the theory that olfaction, like so many other biochemical processes, depends on the existence of chemosensory receptor proteins. This chemosensitivity is in turn a function of stereotaxic molecular properties10.
Op. cit. (note 8), p. 300.
An interesting, and perhaps ultimately more embracing theory of olfaction, is that summarized by Davies11
Ibid., pp. 266ff.
under the sobriquet of “penetration and puncturing” theory. Briefly, the model here is of an odorant molecule of certain shape literally penetrating the lipid layer of the membrane of an olfactory cell. This penetration is effected by the interaction of the polar groups of [page 13] the molecule12
W. Steiner and M. Kaib, “Die Wechselwirkung zwischen Riechstoff und Riechzelle, ein Kernproblem des Riechvorgangs”, Journal of the Society of Cosmetic Chemists 24 (1973), p. 313; “Der asymmetrische Aufbau der Riechstoffmoleküle und die sehr komplexe Grenzfläche zwischen der wässrigen Zellumgebungsflüssigkeit, die das Duftmolekül passieren muss, und der Zellmembran, die aus einem Protein-Lipid-Komplex besteht, lassen eine gerichtete Absorption der Duftmoleküle vermuten, die eine locale Potentialänderung oder eine Änderung der Dielektrizitätskonstante der Membranaussenseite zur Folge haben könnte.
with the electric potential maintained by the membrane13.
On the growing awareness of the importance of electropotentials in cellular membranes, see Loewy & Siekevitz, Cell Structure and Function, 2nd edition (1969), pp. 456ff. (sub Action Potentials).
The physical disruption of the entire lipoprotein membrane organization caused by the offending molecule is then seen as “opening up” holes in the membrane, and thus permitting the activation of the sodium “pump” so that an inflow of Na+ and outflow of K+ relative to the cell is set in motion. A generator current is now set up which will in turn trigger nerve impulses. This theory begins with the necessary stereochemical property of the adsorbed odorant molecule and concludes, in effect, with an electrochemical mechanism for olfaction.
Now consider Lucretius’ further explanation. In talking about the atomic mechanism of taste and smell, the Roman poet has the following to say:
semina cum porro distent, differre necessest
650 intervalla viasque, foramina quae perhibemus,
omnibus in membris et in ore ipsoque palato.
esse minora igitur quaedam maioraque debent,
esse triquetra aliis, aliis quadrata necessest,
multa rotunda, modis multis multangula quaedam.
655 namque figurarum ratio ut motusque reposcunt,
proinde foraminibus debent differe figurae
et variare viae proinde ac textura coercet.
hoc ubi quod suave est aliis aliis fit amarum,
illi, cui suave est, levissima corpora debent
660 contractabiliter caulas intrare palati,
at contra quibus est eadem res intus acerba,
aspera nimirum penetrant hamataque fauces.
[Furthermore, since the seeds differ, the interstices and pathways (which we call pores) must also be different (650) in all the limbs and in the mouth and palate itself. Consequently some (seeds) have to be smaller and others larger, some triangular and others square, many round and many with all kinds of geometric shapes (literally modis multis multangula means “many-cornered in many ways”). The shapes of the pores have to differ in accordance with the demands of (the seeds’) formal configurations and movements (655), and the pathways must vary in accordance with the make-up of their configurations. [page 14] In the case of that which though sweet to some is bitter to others, for him for whom it is sweet it is the very smoothest particles which must enter the channels of the palate in caressing fashion (660). But when people (perceive) the same thing within as bitter, surely it is rough and hooked particles that penetrate the passages.]
Whatever the intuition that underlies Lucretius’ explanation of particulate penetration of membranes, the description itself, though obviously much grosser than, is nevertheless conceptually quite close to, the membrane dynamics envisioned by modern cytochemistry. A modern model is that of a lipoprotein membrane in which two monomolecular layers of protein in the beta14
Op. Cit. (note 7), p. 153.
configuration enclose a central bimolecular layer consisting of primarily steroids and phospholipids. Both steroids and phospholipids are highly polar molecules because of their stereotaxic architecture, and therefore arrange themselves in such a way that their hydrophobic ends face into unit membrane and the hydrophilic parts face outwards15.
Novikoff-Holtzmann, Cells and Organelles (1970), pp. 43ff.
Here a lipid-protein interface is established and, presumably, the possibilities for electro-potential interaction with adsorbed molecules, which will lead to the process described above as “penetration and puncturing” theory.
Lucretius clearly had no conception of the complex (and as yet not fully understood) chemical organization of the lipoprotein membrane, but his analysis of the penetration of variously shaped particles (comparable in modern theory to molecules of rigorously defined stereotaxic conformation) through foramina, or pores, of varying configurations is uncanny in its basic agreement with the modern hypothesis of so-called carrier proteins in the active transport system of the sodium “pump”16.
See Lehninger, op. cit. (note 6), pp. 605ff. And see the striking comment in connection with such biological transport processes in J. Ramsey Bronk, Chemical Biology: An Introduction to Biochemistry (New York 1973), p. 529: “The rapid changes in the permeability of the axon membrane to Na+ and K+ can be likened to the opening and closing of channels or gates, although it is best not to take such analogies too seriously.” (Italics mine.) And be it noted that here we have a scientist explaining his particular view of reality by resorting to that most favorite of poetic devices, the simile!
The generalizations which Lucretius made from his atomic theory about the mechanism of taste and smell are in basic accord with the contemporary models of these phenomena, all depending on electro-chemical interactions at lipoprotein (membrane) interfaces.
Yet for Lucretius this theory was all something in his head, something experimentally without any verification whatsoever. It was not scientific, as we understand the term. To be sure, Lucretius had read the Greek atomists Democritus and Leucippus, and of course Epicurus, and being generally well [page 15] versed in the Greek physical tradition was undoubtedly familiar with Empedocles’ notions about poroi (“passages”) and aporrhoai (“effluxes”) in the latter’s theory of sense perception17.
See G. S. Kirk and J. E. Raven, The Presocratic Philosophers (Cambridge 1957), p. 343.
Like all great minds, Lucretius drew in profitable ways on the past to advance the present into the future. We shall never know how it was that he could come so very close to the views of modern science on these matters (and the tacit assumption here is that “modern science” has a correct answer), relying as he did almost exclusively on analogical arguments from the relative macrocosm of the visible world. I may, however, permit myself to say a word or two about scientific discovery in this connection.
The searchers for “truth” whom society refers to collectively as scientists are notoriously conservative, orthodox, and rigid in their views about the nature of reality. The history of science is filled with examples of theories which, though subsequently recognize as basic to a given discipline and its advancement, were at the time of initial discovery and promulgation contemptuously attributed to undisciplined and fantastic imagination. However Lucretius or his predecessors did come upon their theory of olfaction, and of sensory perception in general, his basic theory lay on the rotting garbage heap of scientific curiosa for some two millennia. It is only during the last generation, with the exponential growth in biochemical knowledge and its application in molecular biology, that it has become possible to recognize that the basis for Lucretius’ theory, as it was stated by himself, is in fact also the basis for one of the central dogmas of modern biochemical thinking: that of “fit”, or lock-and-key, and its refinements in the notion of “induced fit”18.
Daniel E. Koshland, Jr., “Protein Shape and Biological Control”, Scientific American (October 1973), pp. 52ff.
In a most intriguing paper, Stent has addressed himself to the whole question of timing in scientific discovery19.
Gunther S. Stent, “Prematurity and Uniqueness in Scientific Discovery”, Scientific American (December 1972), ppl. 84-93.
His basic thesis is that scientific discovery, like artistic creation, always takes place in the rather narrow context of a definable tradition. Therefore certain new discoveries, such as those of Mendel, for example, or of Avery (who is in effect the first to have demonstrated the significance of DNA – which, incidentally, was discovered by Friedrich Miescher as long ago as 1869!! – as the active principle of genetic material), though published in the scientific literature and generally known among scientists, are simply ignored. This blindness may in part be due to entrenched scientific conservatism, or even to vested interests, but perhaps more to the very human shortcoming that “[…] a discovery cannot be [page 16] appreciated until it can be connected logically to contemporary canonical knowledge20.
Ibid., p. 93.
The new knowledge does not fit, somehow; nothing can be done with it, nothing can be built upon it.
As a poet, Lucretius, like all ancient poets, both Greek and Latin, was acutely conscious of his indebtedness to the literary tradition in which he worked. It was a tradition that went back some seven or eight centuries to Homer and Hesiod. And Hesiod, with his mythopoeic speculations in the Theogony about the organization of reality, stands at the beginning of that lengthy and exciting Greek tradition of concern with the constitution of the universe and the perception of it of which Lucretius the “scientist”21
Lucretius would surely not have thought of himself as a scientist, but as a philosopher, and here too was but following the tradition of the great Greek philosopher-scientist-poets like Aratus, Empedocles, Heraclitus, Anaximander, and others (all of whom as “scientific” poets are in the same Ionian-Greek tradition as the “mythopoeic” poet Hesiod). As I have suggested elsewhere, the two grand estates of science and the arts are both fundamentally concerned with the same objective: the elucidation of reality [see Classical Journal 65.1 (October 1969), p. 26; and 67.3 (February-March 1972), p. 278]. Perhaps Greek and Roman culture sensed the inseparability of these two enterprises more keenly than we do today.
is a direct participant.
I am certainly not arguing that Lucretius knew he had a biochemical explanation for perception that parallels the modern one, but simply suggesting that he, like his contemporaries and followers, did not truly recognize how very right he was. Frequent in his long poem are those almost fanatical asseverations about truthfulness and correctness which can only raise some suspicion about the speaker’s own convictions (e.g. in Book 1.50ff., 370ff., 690ff, 880, etc.).
Nor could one realistically have expected that scientists in the millennia after Lucretius should have picked up on his theories. The difficulty here is, it would seem, in essence that which Stent posits: Lucretius’ theory did not fit in with received knowledge or the generally accepted views of reality. No one could have done anything with the information, fundamentally correct as far as it went, which Lucretius offered; no one could have used it as a basis for further discoveries or advances in the area under consideration.
Hindsight is blind sight in this case: how many theories that have been and are being proposed in full seriousness today are laughed out of court without an honest hearing? Is the proliferation of articles in the popular press (Sunday supplements, Popular Science, to name a few) on a variety of “quack” phenomena (such as ESP, for example) in direct proportion to the conservative biases of editors and editorial consultants of the “legitimate” [page 17] journals who very effectively control what does and does not go into their publications? Stent gives some instances of theories which were initially rejected as fanciful and unscientific, only later to be shown to have been “correct” (read: “fitting the current state of belief and prejudices in the given field”). The accepted view of reality is what “expert” authority allows us to believe to be the case.
The questions which I have extrapolated from this demonstration of the “modernity” of Lucretian thought from the point of view of the molecular biologist have no final solutions. The sciences are at present drowning in the deluge of publications that pour forth in unabated torrents (as any user of any of the scientific abstracting services can personally testify!), and I for one am totally convinced that very little of this work can be truly original or meaningful or even worthwhile. But most of it does fit with the preconceived wisdom of that ubiquitous but perhaps ultimately pernicious group of individuals in all arenas of human endeavor, the “expert” in the field.
And lest I seem, from a smug humanistic woodshed, to be grinding a pessimistic axe with which to decapitate the sacred chickens in the scientific barnyard, let me hastily add that I am only too aware that the situation is not much different, if less intense, in the neighboring farm of the humanities, and for very similar reasons. To take an example close to my own home, the kind of research that was being published in the classical journals at the beginning of this century would in some instances be publishable in today’s journals; but the literary criticism of ancient authors, for example, that is being published today in the classical journals would for the most part not have been accepted then: it is simply too far removed from the entrenched historical biases of the day about doing classical literature. In short, it would not have fit the generally accepted view about how to do classics.
Such relativity in the acceptance of knowledge or information about reality has little if anything to do with the actual truth of the matter. The Ptolemaic-Copernican controversy is a case in point: if, as we today on all available evidence believe, the earth does move around the sun, and not vice versa, it means that this was the case even before Copernicus rashly challenged ecclesiastic authority. No matter what was believed, the actual fact of the solar system’s operation was and is the same. In the case of Lucretius, it is quite clear that he was proposing hypotheses that challenged accepted majority views, not least in his atomic explanations of perception and of the soul’s mortality.
Points raised in this discussion in turn raise further questions about such contemporary allegations as the ability of scientific or literary study to promote openmindedness and a withering of preconceptions, but these are matters which themselves do not fit the present context.
But this ancient Roman poet-philosopher would seem to have been one of the truly precocious and advanced thinkers in his development of a fairly [page 18] consistent theory of perception whose fundamental tenets fit today’s belief about perception at the molecular level. Let me add, in conclusion, that the previous sentence is valid from the vantage point of biochemical belief in 1977. It may or may not be valid ten years from now, for as one researcher in biochemistry has stated: “In biochemistry, the era of model-making has only just begun: it will be unnatural if all our explanations of today will survive intact the test of time.” 22
Peter Farago and John Lagnado, Life in Action: Biochemistry Explained (Vintage Paper, v-906) (March 1973), p. 235.
In describing certain sensory phenomena Lucretius displays an astounding modernity in his conceptualization of the processes involved. What modern science has shown experimentally Lucretius developed by intuition and building on already current notions of the constituents of matter. Since the ancients did not exploit scientific theories for their practical usefulness (as the modern world does), nothing was ever “done” with Lucretius’ notions.