life
LIFE , the popular name for the activity See also:
PECULIAR
peculiar to See also:
PROTOPLASM
protoplasm (q.v.) . This conception has been extended by See also:
ANALOGY (Gr. avaXo-yLa, proportion)
analogy to phenomena different in See also:
KIND (O. E. ge-cynde, from the same root as is seen in " kin," supra)
kind, such as the activities of masses of See also:
WATER
water or of See also:
AIR (from an Indo-European root meaning " breathe," " blow ")
AIR, or ASBEN
air, or of machinery, or by another analogy, to the duration of a composite structure, and by See also:
IMAGINATION
imagination to real or supposed phenomena such as the manifestations of incorporeal entities . From the point of view of exact See also:
SCIENCE (Lat. scientia, from scire; to learn, know)
science life is associated with See also:
MATTER
matter, is displayed only by living bodies, by all living bodies, and is what distinguishes living bodies from bodies that are not alive . See also:
HERBERT (FAMILY)
HERBERT, GEORGE (1593-1633)
HERBERT, HENRY WILLIAM
HERBERT, SIR THOMAS (1606-1682)
Herbert See also:
SPENCER
SPENCER, HERBERT (1820-1903)
SPENCER, JOHN CHARLES SPENCER, 3RD EARL (1782-1845)
SPENCER, JOHNPOYNTZ SPENCER
SPENCER, WILLIAM ROBERT (1769-1834)
Spencer's See also:
FORMULA
FORMULA (Lat. diminutive of forma, shape, pattern, &c., especially used of rules of judicial procedure)
formula that life is " the continuous See also:
ADJUSTMENT (from late Lat. ad juxtare, derived from juxta, near, but early confounded with a supposed derivation from justus, right)
adjustment of See also:
INTERNAL
internal relations to See also:
EXTERNAL
external relations " was the result of a profound and subtle See also:
ANALYSIS (Gr. avci and Meta, to break up into parts)
analysis, but omits the fundamental See also:
CONSIDERATION (from Lat. considerare, to look at closely, examine, generally taken to be from con-, and the base seen in sidus, sideris, a star, the word being supposed to be originally an astrological or astronomical term)
consideration that we know life only as a quality of and in association with living matter . In developing our conception we must discard from consideration the complexities that arise from the organization of the higher living bodies, the See also:
DIFFERENCES, CALCULUS OF (Theory of Finite Differences)
differences between one living See also:
ANIMAL
ANIMAL (Lat. animalis, from anima, breath, soul)
animal and another, or between plant and animal . Such differentiations and integrations of living bodies are the subject-matter of discussions on See also:
EVOLUTION
evolution; some will see in the See also:
PLAY
play of circumambient See also:
MEDIA
media, natural or supernatural, on the simplest forms of living matter, sufficient explanation of the development of such matter into the highest forms of living organisms; others will regard the potency of such living matter so to develop as a mysterious and peculiar quality that must be added to the conception of life . Choice amongst these alternatives need not complicate investigation of the nature of life . The explanation that serves for the evolution of living matter, the vehicle of life, will serve for the evolution of life . What we have to See also:
DEAL
deal with here is life in its simplest See also:
FORM (Lat. forma)
form . The See also:
DEFINITION (Lat. definitio, from de-finire, to set limits to, describe)
definition of life must really be a description of the essential characters of life, and we must set out with an investigation of the characters of living substance with the See also:
SPECIAL
special See also:
OBJECT
object of detecting the differences between organisms and unorganized matter, and the differences between dead and living organized matter . Living substance (see PROTOPLASM), as it now exists in all animals and See also:
PLANTS
plants, is particulate, consisting of elementary organisms living independently, or grouped in communities, the communities forming the bodies of the higher animals and plants . These small particles or larger communities are subject to accidents, internal or external, which destroy them, immediately or slowly, and thus life ceases; or they may See also:
WEAR
wear out, or become clogged by the products of their own activity .
There is no See also:
REASON (Lat. ratio, through French raison)
reason to regard the mortality of protoplasm and the consequent limited duration of life as more than the necessary consequence of particulate See also:
CHARACTER (Gr. xapareri7p, from xap&crew, to scratch)
character of living matter (see See also:
LONGEVITY
LONGEVITY) . Protoplasm, the living material, contains only a few elements, all of which are extremely See also:
COMMON
common and none of which is peculiar to it . These elements, however, form compounds characteristic of living substance and for the most See also:
PART
part peculiar to it . Proteid, which consists of See also:
CARBON (symbol C, atomic weight 12)
carbon, See also:
HYDROGEN [symbol H, atomic weight x-oo8 (0=16)]
hydrogen, See also:
NITROGEN [symbol N., atomic weight 14.01, 0=16]
nitrogen, See also:
OXYGEN (symbol 0, atomic weight 16)
oxygen and See also:
SULPHUR
sulphur, is See also:
PRESENT
present in all protoplasm, is the most complex of all organic bodies, and, so far, is known only from organic bodies . A multitude of See also:
MINOR
MINOR (Lat. for smaller, lesser)
MINOR, ROBERT CRANNELL (1839-1904)
minor and simpler organic compounds, of which carbohydrates and fats are the best known, occur in different protoplasm in varying forms and proportions, and are much less isolated from the inorganic See also:
WORLD
world . They may be stages in the elaboration or disintegration of protoplasm, and although they were at one See also:
TIME (0. Eng. Lima, cf. Icel. timi, Swed. timme, hour, Dan. time; from the root also seen in " tide," properly the time of between the flow and ebb of the sea, cf. O. Eng. getidan, to happen, " even-tide," &c.; it is not directly related to Lat. tempus)
TIME, MEASUREMENT OF
TIME, STANDARD
time believed to occur only as products of Ivingmatter, are gradually being conquered by the synthetic chemist . Finally, protoplasm contains various inorganic substances, such as salts and water, the latter giving it its varying degrees of liquid consistency . We attain, therefore, our first generalized description of life as the See also:
PROPERTY
property or peculiar quality of a substance composed of none but the more common elements, but of these elements grouped in various ways to form compounds ranging from proteid, the most complex of known substances to the simplest salts . The living substance, moreover, has its mixture of elaborate and See also:
SIMPLE
simple compounds associated in a See also:
FASHION (adapted from Fr. facon, agon, Lat. factio, making, facere, to do or make)
fashion that is peculiar . The older writers have spoken of protoplasm or the See also:
CELL (from Lat. cella, probably from an Indo-European kal —seen in Lat. celare, to hide; another suggestion connects the word with Lat. cera, wax, taking the original meaning to refer to the honeycomb)
cell as being in a sense " manufactured articles "; in the more See also:
MODERN
modern view such a conception is replaced by the statement that protoplasm and the cell have behind them a See also:
LONG, GEORGE (1800-1879)
LONG, JOHN DAVIS (1838– )
long See also:
HISTORICAL
historical See also:
ARCHITECTURE (Lat. architectura, from the Gr. ap)(LTEKrwv, a master-builder)
architecture . Both ideas, or both modes of expressing what is fundamentally the same See also:
IDEA (Gr. Ibia, connected with i&eiv, to see; cf. Lat. species from specere, to look at)
idea, have this in common, that life is not a sum of the qualities of the chemical elements contained in protoplasm, but a See also:
FUNCTION
function first of the peculiar architecture of the mixture, and then of the high complexity of the compounds contained in the mixture . The qualities of water are no sum of the qualities of oxygen and hydrogen, and still less can we expect to explain the qualities of life without regard to the immense complexity of the living substance .
We must now examine in more detail the differences which exist or have been alleged to exist between living organisms and inorganic bodies . There is no essential difference in structure . Confusion has arisen in regard to this point from attempts to compare organized bodies with crystals, the comparison having been. suggested by the view that as crystals present the highest type of inorganic structure, it was reasonable to compare them with organic matter . Differences between crystals and organized bodies have no bearing on the problem of life, for organic substance must be compared with a liquid rather than with a crystal, and differs in structure no more from inorganic liquids than these do amongst themselves, and less than they differ from crystals . Living matter is a mixture of substances chiefly dissolved in water; the comparison with the crystals has led to a supposed distinction in the mode of growth, crystals growing by the superficial apposition of new particles and living substance by intussusception . But inorganic liquids also grow in the latter mode, as when a soluble substance is added to them . The phenomena of See also:
MOVEMENT
movement do not See also:
SUPPLY (through Fr. from Lat. supplere, to fill up)
supply any See also:
ABSOLUTE (Lat. absolvere, to loose, set free)
absolute distinction . Although these are the most obvious characters of life, they cannot be detected in quiescent seeds, which we know to be alive, and they are displayed in a fashion very like life by inorganic foams brought in contact with liquids of different See also:
COMPOSITION
COMPOSITION (Lat. compositio, from componere, to put together)
composition . Irritability, again, although a notable quality of living substance, is not peculiar to it, for many in-organic substances See also:
RESPOND
respond to external stimulation by definite changes . Instability, again, which lies at the See also:
ROOT (late O.E. rot, adopted from Scand., cf. Norw. and Swed. rot, Dan. rod; the true O.E. word was wyrt, plant, represented in Ger. Wurz or Wurzel; the ultimate root is the same in both words, and is seen in Lat. radix)
ROOT, ELIHU (1845– )
root of Spencer's definition " continuous adjustment of internal relations to external relations " is displayed by living matter in very varying degrees from the apparent absolute quiescence of frozen seeds to the activity of the central See also:
NERVOUS
nervous See also:
SYSTEM
system, whilst there is a similar range amongst inorganic substances . The phenomena of See also:
REPRODUCTION
reproduction present no fundamental distinction . Most living bodies, it is true, are capable of reproduction, but there are many without this capacity, whilst, on the other See also:
HAND
HAND (a word common to Teutonic languages; cf. Ger. Hand, Goth. handus)
HAND, FERDINAND GOTTHELF (1786-185r)
hand, it would be difficult to draw an effective distinction between that reproduction of simple organisms which consists of a sub-See also:
DIVISION (from Lat. dividere, to break up into parts, separate)
division of their substance with consequent resumption of symmetry by the See also:
SEPARATE
separate pieces, and the breaking up of a drop of See also:
MERCURY
MERCURY (MERCU1uus)
MERCURY (symbol Hg, atomic weight = 2oo)
mercury into a number of droplets .
Consideration of the mode of origin reveals a more real if not an absolute distinction . All living substance so far as is known at present (see See also:
BIOGENESIS (from the Gr. (3ios, life, and yi 'eots, generation, birth)
BIOGENESIS) arises only from already existing living substance . It is to be noticed, however, that See also:
GREEN, A
GREEN, ALEXANDER HENRY (1832—1896)
GREEN, DUFF (1791—1875)
GREEN, JOHN RICHARD (1837—1883)
GREEN, MATTHEW (1696-1737)
GREEN, THOMAS HILL (1836-1882)
GREEN, VALENTINE (1739–1813)
GREEN, WILLIAM HENRY (.1825–1900)
green plants have the See also:
POWER [WILLIAM GRATTAN] TYRONE (1797-1841)
power of See also:
BUILDING
building up living substance from inorganic material, and there is a certain analogy between the building up of new living material only in association with pre-existing living material, and the greater readiness with which certain inorganic reactions take See also:
PLACE (through Fr. from Lat. platea, street; Gr. IrAar6s, wide)
place if there already be present some trace of the result of the reaction . The real distinction between living matter and inorganic matter is chemical . Living substance always contains proteid, and although we know that proteid contains only common inorganic elements, we know neither how these are combined to form proteid, nor any way in which proteid can be brought into existence except in the presence of previously existing proteid . The central position of the problem of life lies in the See also:
CHEMISTRY
CHEMISTRY (formerly "chymistry"; Gr. xvµela; for derivation see ALCHEMY)
chemistry of proteid, and until that has been fully explored, we are unable to say that there is any problem of life behind the problem of proteid . Comparison of living and lifeless organic matter presents the initial difficulty that we cannot draw an exact See also:
LINE
line between a living and a dead organism . The higher " warm-blooded " creatures appear to present the simplest See also:
CASE
CASE, JOHN (d. 1600)
case and in their life-See also:
HISTORY
history there seems to be a point at which we can say " that which was alive is now dead." We See also:
JUDGE (Lat. judex, Fr. juge)
judge from some See also:
MAJOR
MAJOR (Lat. for " greater ")
MAJOR (or MAIR), JOHN (1470-1550)
major See also:
ARREST (Fr. arrester, arreeter, to stop or stay)
arrest of activity, as when the See also:
HEART
HEART, LUNG
heart ceases to See also:
BEAT (a word common in various forms to the Teutonic languages; it is connected with the similar Romanic words derived from the Late Lat. battere)
beat . Long after this, however, various tissues remain alive and active, and the event to which we give the name of See also:
DEATH
death is no more than a superficially visible See also:
STAGE (Fr. 6/age; from Lat. stare, to stand)
stage in a See also:
SERIES (a Latin word from serere, to join)
series of changes . In less highly integrated organisms, such as " See also:
COLD (in O. Eng. cald and ceald, a word coming ultimately from a root cognate with the Lat. gelu, gelidus, and common in the Teutonic languages, which usually have two distinct forms for the substantive and the adjective, cf. Ger. Kolte, kalt, Dutch koude
cold-blooded " vertebrates, the point of death is less conspicuous, and when we carry our observations further down the See also:
SCALE
SCALE (1) A
scale of animal life, there ceases to be any salient phase in the slow transition from life to death . The distinction between life and death is made more difficult by a consideration of cases of so-called " arrested vitality." If See also:
CREDIT (Lat. credere, to believe)
credit can be given to the stories of See also:
INDIAN
Indian fakirs, it appears that human beings can pass voluntarily into a See also:
STATE
STATE, GREAT OFFICERS OF
state of suspended animation that may last for See also:
WEEKS, EDWIN LORD (1849-1903)
weeks . The state of involuntary See also:
TRANCE (through the French, from Lat. transitus, from transire, to cross, pass over)
trance, sometimes mistaken for death, is a similar occurrence .
A . See also:
LEEUWENHOEK, or LEUWENHOEK, ANTHONY VAN (1632–1723)
Leeuwenhoek, in 1719, made the remarkable See also:
DISCOVERY
discovery, since abundantly confirmed, that many animalculae, notably tardigrades and rotifers, may be completely desiccated and remain in that See also:
CONDITION (Lat. condicio, from condicere, to agree upon, arrange; not connected with conditio, from condere, conditum, to put together)
condition for long periods without losing the power of awaking to active life when moistened with water . W . Preyer has more recently investigated the matter and has given it the name " anabiosis." Later observers have found similar occurrences in the cases of small nematodes, rotifers and bacteria . The capacity of plant seeds to remain dry and inactive for very long periods is still better known . It has been supposed that in the case of the plant seeds and still more in that of the animals, the condition of anabiosis was merely one in which the See also:
METABOLISM (from Gr. ,uera(3oXh, change)
metabolism was too faint to be perceptible by See also:
ORDINARY (med. Lat. ordinarius, Fr. ordinaire)
ordinary methods of observation, but the elaborate experiments of W . Kochs would seem to show that a See also:
COMPLETE
complete arrest of vital activity is compatible with viability . The categories, " alive " and " dead," are not sufficiently distinct for us to add to our conception of life by comparing them . A living organism usually displays active metabolism of proteid, but the metabolism may slow down, actually cease and yet reawaken; a dead organism is one in which the metabolism has ceased and does not reawaken . Origin of Life.—It is See also:
PLAIN (O. Fr. plain, from Lat. plenum)
plain that we cannot discuss adequately the origin of life or the possibility of the artificial construction of living matter (see See also:
ABIOGENESIS
ABIOGENESIS and BIOGENESIS) until the chemistry of protoplasm and specially of proteid is more advanced . The investigations of O . Butschli have shown how a See also:
MODEL (0. Fr. modelle, mod. modele; It. modello, pattern, mould; from Lat. modus, measure, standard)
model of protoplasm can be manufactured .
Very finely triturated soluble particles are rubbed into a smooth See also:
PASTE (O. Fr. paste, modern pate, Late Lat. pasta, whence also in Span., Port. and Ital., from Gr. 1r&vrrl or 1raara, barley porridge, or salted pottage, ir&ao'ety, to sprinkle with salt)
paste with an oil of the requisite consistency . A fragment of such a paste brought into a liquid in which the solid particles are soluble, slowly expands into a See also:
HONEYCOMB
honeycomb like foam, the walls of the See also:
MINUTE
MINUTE (Lat. minutes, small; minuere, to make less)
minute vesicles being films of oil, and the contents being the soluble particles dissolved in droplets of the circumambient liquid . Such a model, properly constructed, that is to say, with the vesicles of the foam microscopic in See also:
SIZE
size, is a marvellous See also:
IMITATION (Lat. imitatio, from intitari, to imitate)
imitation of the See also:
APPEARANCE (from Lat. apparere, to appear)
appearance of protoplasm, being distinguishable from itonly by a greater symmetry . The nicely balanced conditions of See also:
SOLUTION (from Lat. solvere, to loosen, dissolve)
solution produce a state of unstable See also:
EQUILIBRIUM (from the Lat. aequus, equal, and libra, a balance)
equilibrium, with the result that internal streaming movements and changes of shape and changes of position in the model simulate closely the corresponding manifestations in real protoplasm . The model has no power of recuperation ;in a comparatively See also:
SHORT, FRANCIS JOB (1857– )
short time equilibrium is restored and the resemblance with protoplasm disappears . But it suggests a method by which, when the chemistry of protoplasm and proteid is better known, the proper substances which compose protoplasm may be brought tpgether to form a simple kind of protoplasm . It has been suggested from time to time that conditions very unlike those now existing were necessary for the first appearance of life, and must be repeated if living matter is to be constructed artificially . No support for such a view can be derived from observations of the existing conditions of life . The chemical elements involved are abundant; the See also:
PHYSICAL
physical conditions of temperature pressure and so forth at which living matter is most active, and within the limits of which it is confined, are See also:
FAMILIAR (through the Fr. familier, from Lat. familiaris, of or belonging to the familia, family)
familiar and almost See also:
CONSTANT, BENJAMIN (1845-1902)
constant in the world around us . On the other hand, it may be that the initial conditions for the See also:
SYNTHESIS (Gr. a6vOeacs, from avvrcBivac, to put together)
synthesis of proteid are different from those under which proteid and living matter display their activities . E . Pfluger has argued that the analogies between living proteid and the compounds of See also:
CYANOGEN (Gr. ebavos, blue 'yevvav, to produce), C2N2
cyanogen are so numerous that they suggest cyanogen as the starting-point of protoplasm .
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