Yesterday, someone made a great point on LinkedIn. In the comments of one of my posts, they wrote, "we can't even agree what soil is". As someone who has dedicated not a insignificant amount of time considering this fact, it got me thinking about why we need to agree on what 'soil' is in the first place. Why do we even need scientific definitions?

A definition separates something from something else

A definition should tell us what something is, but also eludes to what it is not. Aristotle said a definition is to describe the kind's essential or defining features and these kinds must exist in all of its variations. Perhaps something to think about when it comes to defining soil.

An unclear definition can hinder the science

According to Caws (1959) definition is required to 'develop and clarify' theories. If we don't know what we are studying, how can we fully understand how it behaves and what it does?

A definition is slightly different from a concept

Definitions are not agreed upon, they are what is. Arguably then, because we have to agree upon what soil is, it is a concept or theory, not a definition. To that same extent a scientific definition does not describe what something does or how it is measured. Nor is it classification. (See Hibbard, 2019 for further discussion on the complexity of 'essential - exists in all iterations - and accompanying - exists in some iterations only - features').

Consistent definition usage helps those outside of the subject understand it better

Does only Earth have soil? Should we say Mars has soil? If we don't know, it makes communicating Martian science much more challenging, and unclear.

I quickly realised there is a wormhole of 'definition-related' literature, but it's worth dipping into if you are in the business of defining what a soil is.