Matter and Form (BPC)

Turning to two terms that will help us think about composite entities and their constituents: Matter and Form

Matter matters because the kind of constituents a composite entity is made out of conditions the nature of the composite entity. For example, the bricks as part of a castle—heavy bricks—might make the castle stronger if the enemy uses explosives against it. The contituent stuff that the castle is made of conditions its properties—in this case, the strength of the castle.

To further exemplify this, we can see that combinations of different substances (different matters) create different compounds. Oxygen and metal make rust. Oxygen and hydrogen make water. Different elements in combination create different compounds. If we want pure oxygen, perhaps for medical purposes, we can melt rusty metal. If we want to prevent a metal from rusting, we have to somehow prevent it from binding with oxygen. The concept of matter, the practice of identifying the parts that something is made out of, is a key aspect of understanding why things are the way they are.

Form is important because the relationships between constituents condition the nature of a composite entity. The particular way the sticks are interwoven in a wicker fence will condition the properties of the fence. If they're clenched tight against one another, the fence will be strong. If they're only loosely woven, then the fence will be weak.

The concept of form helped chemists identify the property of isomers. Isomers are different compounds that are somehow different despite being made of the same elements in the same mass ratios. Since their matter is the same, it was hypothesized that their form, the relationships between the constituents, are somehow different. Specifically, different isomers of a compound are said to have different spatial arrangements of their constituent atoms.