MEALYWING. 231 MEANING. known, of which more than 50 occur in the United States. The most destructive species is Aleyrodes ritri, wiiich attacks the orange and lemon in Florida and Louisiana, and causes the leaves to turn yellow and die. They secrete a considerable amount of lioneydew, which attracts the spores of smut fuiif,'!. resulting ultimately in the blackening of the foliage of the orange trees. MEAN (OF. meien, moien, Fr. moycn, from Lat. mcdiaiius, middle, from medius, middle). In mathematics, a term interpolated between two other terms of a series. The arithmetic mean a + b of twc riuantities a, b, is — ^ — ; their geometric mean is W ub, and their harmonic mean is -. a-- b The arithmetic mean is gieater than the geo- metric mean, and tlie latter is greater than the harmonic mean. In averaging observed results of physical experiments, the mean result may be found by dividing the sum of the observed re- sults by the number of observations. But in ease the observed results are not regarded as equally accuiate, certain numbers may be as- signed to these results representing their relative ac<-uracy; e.g. four men. A. B. C, D. have deter- mined the area of a triangle and found 10.50, Ift.T."), 20. and 20.25 square meters, respectively. If the relative accuracy of their work may be represented by the numbers 3, 2, 2, 4 respective- ly, the area of the triangle will be taken as: 3-19.50 + 2-19.75 + 2-20 + 4-20.2.5 _ , q ni 3 + 2 + 2-f4 -19.J1. For furtlier jn-actical methods of averages, see Least Sqiabes. JIethod of. MEAN'DEB. A river of Asia Minor. See il.tAXDEl!. MEANING (from mean, AS. viwnan, OHG. mrinan, Ger. meinen, to think: connected with OChureh Slav, meniti, Skt. man, to think). The mental processes that constitute the unanalyzed consciousnesses of ordinary, everyday experience are always surcharged with meaning or signifi- cance. Mind, as it is given, is mind in function; mental stuff that stands for, represents, sym- bolizes, refers to, objects and events in the out- side world. The value and validity of such objective reference form a question for epistemol- opj-. (See Knowledge, Theory of.) But the psychologist, after he has analyzed consciousness into its simplest structural elements (see Ele- JIKXTS, C'oxsciots), and has traced the forma- tinn of the more complex processes from connec- tions of the elements (see .ssoci.Tiox OF Ideas; Fisioj;) — after, that is to say, he has analyzed and reconstructed mind without regard to mind's significance and meaning — is met by the ques- tion: What is, in psychological terms, the vehicle of meaning? How did meaning get into mental ])rocesses? What are the processes, or what the aspects of process, that 'carry' the meaning of a given psychical coni])lex'; As regards what we may term the 'origin' of meaning, only two views seem to be possible. Mind may, at its first appearance in the world, have been meaningless; and meaning may have been 'worked into' it, in the course of natural evolution. This view, however, presents extreme dilllculties. It is not hard to conceive that the me.aningful or significant aspect of mental proc- ess should have been refined and differentiated under the operation of natural selection; but it is impossible to form any definite idea of the way in which an organism should lay hold of meaningless nuiterial, and press it into service as meaningful. We have, in other words, a recur- rence of the ditliculty which characterizes hetero- genetic will theories (see Will) : we can no more derive meaning from the unmeaning than we can derive voluntary action from the physiological retiex. The alternative view is thus forced upon us, that meaning did not 'get into' mind, for the simple reason that it was always there. Mind is 'struck out' in the interaction between organism and natural environment: and, arising as it did, could do nothing else than mean, A mind that should not mean is a contradiction in terms: we may abstract from meaning, in our laboratory dissections of consciousness, as we abstract from life in the anatomical laboratory; but a mean- ingless mind is not a mind, as a dead organism is not an organism. See Noetic Con'sciousxess. When, therefore, we come to our other ques- tion, regarding the processes or aspects of proc- ess that form the vehicle of meaning, we find an answer ready to our hand, ilental process is intrinsically meaningful; any process can carry meaning. And it may be remarked, by the way, that tills fact largely accounts for the short cuts in mental function, the substitutions of proc- ess for process within a functional formation (like that of space perception, e,g. ), that make mental analysis so dilficult, and render a lapse into the "psychologist's fallacy' a matter of siich fatal ease. (See Ixtkospectiox. ) Ou the other hand, as mind advances in complexity, it be- comes necessary that arrangements be made (if we may use that expression) for devolving the carri.age of meaning upon determinate constitu- ents of consciousness. In the absence of such arrangements the grossest confusion would result. To take a simple instance: there are many words which, as the spelling-books say, are pronounced alike but spelled difl'erently. "The rain ( reign ) is over at last ! " What is it that makes one hearer think of the weather, and another of the Queen of England ? Why does the auditory stimulus mean rain to the one and reign to the other ? In replying to this question, we nmst remem- ber that consciousness is a complex atVair, and that its range is wider than the range of atten- tion (q.v. ). Hence there will alwaj-s be, in a given consciousness, a certain 'focal' process or group of processes, corresponding to the range of attention, and a group or groups of obscurer 'marginal' processes which lie beyond that range. Now. as Bagley puts it, the "same symbol [e.g. word] arouses at difl'erent times focal references which may be uniform or disparate, consistent or inconsistent; and yet the meaning of the symbol, in combination with other symbols, is perfectly unequivocal." The required uniformity is fur- nished, and the inconsistencies compensated, by the marginal context: "the meaning is a function of the more transitive parts of consciousness, the fringe or relations which we feel surroTinding the image" (.Tames). The 'armngement' spoken of above consists, then, in the relegation of the meaning-function to the background of conscious- ness; that constancy of adaptation to the outside world, which becomes impossible to the focal processes as mental development advances and
