Same and Other

Every act of knowing begins with telling one thing from another and recognizing a thing as the one it is. Same and Other names that double operation, and the related questions of identity and diversity, likeness and unlikeness. It is a great idea for the Harvard Classics because it runs through nearly every field these books touch. It appears in the psychology of perception and memory, in the theory of art and taste, in friendship and politics, in the riddle of the self that persists through change, and in the natural sciences, which must decide when two samples of matter or two animals are the same. The question is old enough to appear in Homer and Plato. It is also new enough that Darwin and Faraday reformulated it with new instruments. And some of its answers point in opposite directions: some authors stress the identity hidden beneath difference, others the difference hidden beneath every likeness.

The most elementary claim is that the mind lives by comparing. In the Phaedo, Plato has Socrates argue that recollection is set off by things both like and unlike what they recall. The same sensible equals may look equal at one time and unequal at another, which suggests that our idea of equality is not drawn from them¹. Rousseau’s Savoyard Vicar makes a related point in the language of the moderns. Sensations that were alike could not be told apart, nor could we know that what we touch is the same object we see, unless the mind actively compared them². Comparison is thus a deed of judgment, not a passive receiving.

Once comparison is granted, finer distinctions follow. Johnson separates near identity from the resemblance that holds across things otherwise unlike³. Burke warns that blending two qualities does not make them the same, since the distinct qualities remain within the mixture⁴. Pascal turns the habit of comparison toward the moral life. One should measure oneself not against other men but against Christ, and measured against oneself one appears abominable⁵.

Comparison also gives pleasure, and the critics ask which kind of comparison pleases most. Burke holds that the mind delights more in tracing resemblances than in finding differences. Resemblance produces new images and flatters the imagination, and in this pleasure men are nearly equal, provided their knowledge is equal^6,7. In the theory of the sublime he adds that uniformity sustains an impression, while the alternation of dissimilar things destroys it⁸.

Coleridge refines the point into a principle of art. Imitation, as distinct from mere copying, requires that likeness and difference coexist and be reconciled in one work⁹. The pleasure we take in art arises from this union of sameness with variety¹⁰. Wordsworth applies a similar logic to literary kinds. Poetry and prose, he argues, are the same in substance and kindred in their affections, and they differ not even in degree¹¹. Here an apparent difference of kind is denied altogether.

A more philosophical controversy asks whether different persons ever see the same thing. Berkeley’s Philonous answers that the dispute is largely about the word “same.” Our ideas vary continually, and if every variation counted as a new thing there would be endless individuals. So we group similar ideas under one name¹². Whether a house pulled down and rebuilt is the same house depends on how we choose to use the term¹³. Disputants about identity and diversity may therefore differ in words while agreeing in thought. And the objection that no two people see the same thing, if it is an objection at all, strikes the materialist as hard as the idealist¹⁴. Emerson, writing of the English mind, sees this as a lasting division of temperaments: the strife between those who perceive identity everywhere and those who perceive discrepancies¹⁵.

On one side of that strife stand writers who insist that no two things are ever exactly alike. Sir Thomas Browne declares that no two faces, and indeed no two things, are perfectly alike. Some difference always prevents identity, so that likeness implies diversity even in the resemblance of man to God¹⁶. Raleigh says that nature triumphs in dissimilitude, giving every man a different face, mind, fancy and inclination¹⁷. Pascal notes that not even two grapes or two bunches are the same, and that voices and gaits vary without end¹⁸. Johnson, laboring over his dictionary, confesses that ideas of the same family may differ so slightly that words cannot express the difference, though the mind perceives it¹⁹.

The same theme appears in other registers. Mazzini distinguishes Byron and Goethe by two forms of individuality, the subjective and the objective²⁰. Darwin records that the Fuegians readily perceived differences between Jemmy, York and the Europeans that a casual eye might miss²¹. Darwin also gives the doctrine a scientific edge. An extinct form, once lost, could never be recreated identically, just as fantail pigeons could not be bred again from some other stock²².

If everything differs, likeness can still serve as evidence. Two scenes from the ancient poets show this. In the Odyssey, the old nurse Eurycleia notices that the stranger resembles Odysseus in bearing, voice and feet, and the reader knows the likeness is identity²³. In Aeschylus, Electra compares the lock of hair and the footprints at her father’s tomb with her own, and from the resemblance she infers her brother’s presence²⁴. Recognition rests on the inference from like to same, an inference the poets present as fallible but powerful.

In human relations the question becomes one of balance. Emerson holds that friendship requires a mean between likeness and unlikeness. A friend must remain himself and not become an echo, while beneath their differences the two share a deep identity²⁵. Elsewhere he speaks of an identity that makes us all one and reduces great intervals to nothing²⁶.

The religious and political books ask whether men are fundamentally alike or unlike. In the Bhagavad-Gita the Lord declares himself alike to all, whatever their caste, sex or birth, and says that all may reach the highest path²⁷. Rousseau, by contrast, distinguishes the natural or physical inequality among men from the moral or political inequality that convention establishes²⁸. Both see a sameness deeper than visible difference, but they locate it differently.

Personal identity draws the idea into its most dramatic form. The comic and tragic writers stage crises in which a person doubts whether he is himself. Don Quixote’s neighbor insists that he is plain Master Quixada and none of the heroes he names. Quixote replies that he may be all of them²⁹. Calderón’s Segismund, waking from what he is told was a dream, fears that he has drifted from the self he was yesterday and asks whether he is the same person³⁰. The Grimms’ Clever Elsie, jingling with bells, cannot tell whether she is herself and asks whether Elsie is within³¹. Andersen pushes the doubt furthest. The learned man’s shadow returns as a separate and independent man, until master and shadow can hardly be told apart³².

Against these crises, the philosophers affirm that something abides. Plato’s Socrates, admitting that he is small compared with Simmias, remains the same small person; only his relation has altered³³. Pascal illustrates the notion of numerical identity by asking whether the same body, or the same river, might be in China³⁴. Schiller states the principle outright. The person remains the same through all changes of condition, so that we are always ourselves³⁵, and personality remains identical with itself through every change of state³⁶.

The Buddhist writings take a third position, one that neither the Greeks nor the moderns in this collection state. Asked whether the doer of a deed and the one who reaps its result are the same, the teacher rejects both answers: they are not the same, nor are they different³⁷. The reborn being is neither identical with the one who died nor wholly other, as a light kindled from a light is neither the old flame nor unrelated to it³⁸. The new name and form differs from the old yet springs from it, like later fire from earlier³⁹, or like the grown woman from the girl she was⁴⁰. For this reason evil deeds are not escaped by death⁴¹. The doctrine is generalized to every causal series. If absolute sameness held, milk could never become sour cream, and if absolute diversity held, the cream would not come from the milk⁴². The bearer of fruit in such a series is neither the same as nor other than what went before, just as the power in seeds produces the plant⁴³. Schiller’s abiding personality and this causal continuity without a substantial self are the clearest opposition the collection offers on the question of who we are.

Natural science treats sameness in its own way, as identity of kind or substance under diverse appearances. Faraday insists that water, whether it comes from a candle, a lamp, a river or the ocean, is one and the same thing, unchanged in any state^44,45,46. Carbonic acid is likewise the same substance whether drawn from a candle, marble or chalk^47,48. At the largest scale he argues that chemical force, heat, electricity and light are one power in different forms⁴⁹. Helmholtz compares granular with crystallized ice, and marble with spar, to show the same material in different arrangements⁵⁰. Pascal’s mathematical writings supply the complementary distinction. Unity differs from number only in name, but an indivisible point differs from extension in kind⁵¹. Because indivisibles are not of the same species as extension, they cannot compose it⁵².

In biology the boundaries of kinds are harder to draw. Aesop’s bat, claiming to be beast or bird as suits it and belonging to neither, is the fabulist’s emblem of the ambiguous creature⁵³. Darwin makes that ambiguity a principle. Individuals of one species may differ greatly, as males from females, castes of insects from one another, and larvae from adults, yet remain one species^54,55. Varieties differ slightly from their parents, and accumulated divergence yields well-marked species⁵⁶. In the end, degrees of difference decide whether forms are ranked as varieties or species⁵⁷. Behavior can be closely alike both within one species and between distinct species⁵⁸. Illegitimate offspring of plants closely resemble hybrids⁵⁹, and hybrids and mongrels resemble their parents by the same laws^60,61. Darwin concludes that no essential difference separates species from varieties.

The Beagle journal shows the problem in the field. Darwin weighs whether two allied mocking-birds are the same or distinct by fine shades of habit and appearance⁶². He compares a fossil rodent with the living tucutuco, which it resembles yet differs from⁶³. He asks whether island forms are varieties or species when they are analogous to, yet distinct from, continental forms⁶⁴. In the Origin he observes that the likeness and unlikeness of faunas across regions cannot be explained by physical conditions⁶⁵. He also notes that plants on distant mountain heights prove to be the same species, or varieties, or forms representing one another⁶⁶.

Darwin’s most important refinement separates two kinds of likeness. Homology is resemblance from common origin. Analogy is resemblance of function without it⁶⁷. The eyes of different animals may look alike while hiding fundamental differences of structure⁶⁸. Conversely, organs that look widely different may be homologous⁶⁹. Whales resemble fishes, and certain marsupials resemble mice, only by analogy, which is distinct from real affinity⁷⁰. Indeed, the same character may be merely analogical between groups yet a mark of true affinity within one⁷¹. The embryos of lizard, bird and mammal were so alike that von Baer could not tell them apart, resembling in youth and diverging in maturity⁷². The common plan of hand, wing, fin and leg is explained by descent from a common ancestor⁷³. Even in South America Darwin found a bird resembling quails in habit and snipes in flight, whose true affinity only its skeleton could settle⁷⁴. With this, likeness is no longer a simple datum. It becomes a historical clue that must be interpreted.

The same tension extends to peoples. Tacitus believed the Germans native to their land and unmixed with other nations⁷⁵, a pure people all alike in physique⁷⁶. Emerson answers that races shade imperceptibly into one another, which is why writers count them differently⁷⁷. Pure descent, he says, is an illusion; the English are a composite, better than any of the stocks that formed them⁷⁸. Freeman qualifies the matter. Infusions of new blood that are assimilated modify the personality of the absorbing people without changing it, though a people’s origins may differ from its apparent identity⁷⁹. The Swiss nation is an exception among nations defined by language, yet close to them in likeness⁸⁰. Kinship of tongues must also be distinguished from mutual intelligibility, which marks off races, nations and dialects⁸¹.

Across these books the question has moved from the forum of recognition, as with Eurycleia’s touch and Electra’s comparison, to the laboratory and the herbarium. It has not been closed. Browne’s claim that every likeness hides a difference and Faraday’s claim that water is everywhere the same are not contradictory, but they reflect opposite habits of attention. Berkeley’s suspicion that disputes about sameness are often verbal returns in Darwin’s admission that ranking a form as a species or a variety is a matter of degree. And the self remains contested between Schiller’s abiding personality, the Buddhist series that is neither same nor other, and the comic heroes who wonder whether they are themselves at all.