Concept
Quantity
Overview
Quantity or amount is a property that includes numbers and quantifiable phenomena such as mass, time, distance, heat, angle, and information. Quantities can commonly be compared in terms of "more", "less", or "equal", or by assigning a numerical value multiple of a unit of measurement. Quantity is among the basic classes of things along with quality, substance, change, and relation. Some quantities are such by their inner nature (as number), while others function as states (properties, dimensions, attributes) of things such as heavy and light, long and short, broad and narrow, small and great, or much and little.
Under the name of multitude comes what is discontinuous and discrete and divisible ultimately into indivisibles, such as: army, fleet, flock, government, company, party, people, mess (military), chorus, crowd, and number; all which are cases of collective nouns. Under the name of magnitude comes what is continuous and unified and divisible only into smaller divisibles, such as: matter, mass, energy, liquid, material—all cases of non-collective nouns.
Along with analyzing its nature and classification, the issues of quantity involve such closely related topics as dimensionality, equality, proportion, the measurements of quantities, the units of measurements, number and numbering systems, the types of numbers and their relations to each other as numerical ratios.
Overview adapted from Wikipedia (CC BY-SA 4.0; see the article history for authors).
In the original texts
Passages from public-domain books where Quantity is discussed.
100.] Quantity, as we saw, has two sources: the exclusive unit, and the identification or equalisation of these units. When we look therefore at its immediate relation to self, or at the characteristic of self-sameness made explicit by attraction, quantity is Continuous magnitude; but when we look at the other characteristic, the One implied in it, it is Discrete magnitude. Still continuous quantity has also a…
Georg Wilhelm Friedrich Hegel, The Logic of Hegel
names the idea; a chapter is titled for it; states what it is; opens on it
Nor is there any other kind of quantity, of all that have been mentioned, with regard to which variation of degree can be predicated. The category of quantity, therefore, does not admit of variation of degree. The most distinctive mark of quantity is that equality and inequality are predicated of it. Each of the aforesaid quantities is said to be equal or unequal.
Aristotle, The Categories
names the idea; states what it is; author linked in the graph; opens on it
Thus, when one quantity is to be divided by another, the signs which denote both are placed in the form peculiar to the operation of division; and thus algebra, by means of a symbolical construction of quantity, just as geometry, with its ostensive or geometrical construction (a construction of the objects themselves), arrives at results which discursive cognition cannot hope to reach by the aid of mere conceptions.
Immanuel Kant, The Critique of Pure Reason
names the idea; states what it is; opens on it
Does quantity, on entering into matter extend matter, so as to give it magnitude? By no means, for matter had not been condensed.
Plotinus, Plotinos
names the idea; states what it is; opens on it
And this is evidently a contradiction in terms. To sum the matter up, the term "infinite" always relates to the notion of quantity. Quantity is that which is essentially capable of increase or decrease. There is then an infinity of quantity; there is no quantity which is the absolute limit to quantity. Such a quantity would be incapable of increase, and hence contradictory to quantity.
John Dewey, Leibniz's New Essays Concerning the Human Understanding
names the idea; states what it is
Philosophers who discussed Quantity
Related ideas
- Quality (philosophy)
- Infinitesimal
- Geometry
- Information
- Mass
- Heat
- Quantum
- Number
- Person
- Ontology
- Euclid's Elements
- Set (mathematics)
- Substance theory
- Time
- Aristotle
- Variable (mathematics)
- Noun
- Gender
- Property (philosophy)
- Calculus
- Circle
- A priori and a posteriori
- English language
- Euclid
Place in the tradition
Part of Ontology.