Let us take, for example, two statements ex-pressed orally: (1) "Today is a warm day", and (2) "Today the temperature will be 95 degrees F.". Both are similar statements, but 1 is qualitative, whereas 2 is quantitative. We are able to assess the temperature in the qualitative form by using our senses or by utilizing a thermometer to determine the temperature precisely in the quantitative form.
This simple example shows, that quality and quantity are related and sometimes are interchangeable. This exchangeability of quality and quantity was a problem for many philosophers dating back to the ancient Greeks. Numerous theories have ex-isted which have gone through evolutionary changes right up to the time of Ein-stein's new theories in physics. The ancient Greeks thought, that matter has inher-ent qualities, like hardness or color. Atomic theory indicates that the atoms have no quality like hardness or color. Only structures of elements can get qualitative properties. .
B. QUALITY VERSUS QUANTITY VERSUS SUBSTANCE.
The above mentioned statements indicate that there are differences and commonal-ties between quality, quantity, and substance. Philosophers and physicists found, that: .
• In language, quality is located in the attribute to the substance and describes properties of matter.
• Quality and quantity are related and are sometimes exchangeable.
• We use our senses or gauges to determine quality.
• There is no single definition of quality.
• Quality does not change (warm is always warm), but substance changes quality, e.g. the air can be warm or cold.
• Substance and its quality are not easily separable because all substances have qualities. We are only able to detect substances by detecting their qualities.
• Quantity does not have a antithetical element; quality does. There is no anti-thetical number for the number 100; but the antithesis of warm is cold, of solid is liquid etc.