Variability Quotes
It is willingly granted that by cultivation the origination of new varieties is favored, and that by man's labor many varieties are acquired which, under natural conditions, would be lost; but nothing justifies the assumption that the tendency to formation of varieties is so extraordinarily increased that the species speedily lose all stability, and their offspring diverge into an endless series of extremely variable forms. Were the change in the conditions the sole cause of variability we might expect that those cultivated plants which are grown for centuries under almost identical conditions would again attain constancy.
Gregor Mendel
Based upon evidence such as already presented, it appears feasible to set up criteria by which to determine when assignable causes of variation in quality have been eliminated so that the product may then be considered to be controlled within limits. This state of control appears to be, in general, a kind of limit to which we may expect to go economically in finding and removing causes of variability without changing a major portion of the manufacturing process as, for example, would be involved in the substitution of new materials or designs.
Walter A. Shewhart
What Lamarck then foretold has come to pass; the more new forms have been multiplied, the less are we able to decide what we mean by a variety, and what by a species. In fact, zoologists and botanists are not only more at a loss than ever how to define a species, but even to determine whether it has any real existence in nature, or is a mere abstraction of the human intellect, some contending that it is constant within certain narrow and impassable limits of variability, others that it is capable of indefinite and endless modification.
Charles Lyell
Given my present belief in the much greater range of variability as to both order and kind of complexity in the world's musics versus the world's languages, I can hardly imagine how a model developed really satisfactorily for the detailed structureal explanation of one musical language is so easiy modified to another, and all the more so if the original model be evolved from linguistics rather than from the musical disciplines.
Harold Powers
In order for there to be a variable quantity in some mathematical study, the domain of its variability must strictly speaking be known beforehand through a definition. However, this domain cannot itself be something variable, since otherwise each fixed support for the study would collapse. Thus this domain is a definite, actually infinite set of values. Hence each potential infinite, if it is rigorously applicable mathematically, presupposes an actual infinite.
Georg Cantor
The manner in which time and space are bound up with each other in the four-dimensional continuum is variable. It is difficult to express this variability of the cross-connections between space and time in simple language, and different interpretations of it are possible, corresponding to different mathematical transformations of the fundamental line-element, e. g. a different choice of the variable which we interpret as "time." Perhaps the best way we can express it is by saying that the solution of the field-equations of the theory of relativity shows that there is in the universe a tendency to change its scale, which at the present time results in an expansion, but may perhaps at other times become, or have been, a shrinking. This is true of the grand scale model of the universe.
Willem de Sitter
We all endeavour, as Spinoza says, to persist in our own being; and that endeavour is, he adds, the very essence of our existence. When, therefore, we find that what delighted us once can still delight us: that though the objects of our admiration may be intermittent, yet they move in fixed orbits, and their return is certain, these reappearances will suggest that we have after all maintained something of our own integrity; that a sort of system lies beneath the apparent variability of our interests; that there is, so to speak, a continuity within ourselves, a core of meaning which has not disintegrated with the years.
Logan Pearsall Smith
Gärtner by the results of these transformation experiments, was led to oppose the opinion of those naturalists who dispute the stability of plant species and believe in a continuous evolution of vegetation. He perceives in the complete transformation of one species into another an indubitable proof that species are fixed within limits beyond which they cannot change.
Although this opinion cannot be unconditionally accepted, we find on the other hand in Gartner's experiments a noteworthy confirmation of that supposition regarding variability of cultivated plants which has already been expressed.
Gregor Mendel
But his genetic and physical inference from cases of ethnic durability cannot account for the considerable variability, wide range and frequent absorptions and dissolutions of instances of ethnic affiliation, and the fact that many ethnies have undergone large-scale changes of culture and, in some cases, of demography. This is the case even in such a culturally long-lived example as the Greeks, where undoubted evidence of massive rupture of demographic continuity by the influx of Albanians and Slavs on the Greek mainland from the sixth to eighth centuries AD and of considerable, though not complete, culture change after the conversion to Orthodoxy, call into question the continuity and influence of a common ancient Greek biological and genetic inheritance on modern Greeks.
Anthony D. Smith
How far away from the earth are those remotest of stars: they are beyond the reach of eye, or man's devices, or man's thought. What an absurdity is this motion (of spheres). He also argues for the extreme variability of the distance to the various heavenly bodies and states that situated "in thinnest aether, or in the most subtle fifth essence, or in vacuity - how shall the stars keep their places in the mighty swirl of these enormous spheres composed of a substance of which no one knows aught?
William Gilbert (astronomer)