XXII. Classes of Concepts

Thus far, concepts have been discussed in a general manner: they are the mental ideas of the general qualities of a class of things. And whereas a percept arises from the senses, a concept is a purely mental creation whose only existence is in the world of ideas.

Generally speaking, there are two classes of concepts:

  1. Concrete concepts that correspond to a class of things that can be perceived by the senses (nouns)
  2. Abstract concepts that derive from the qualities common to a class of things that cannot be perceived by the senses (verbs and adjectives)

In general, the broader the class of things embraced by a concept, the fewer the number of qualities (concrete or abstract) it contains that qualify it is a member of that class, and the more abstract the qualities become. That is, the class of "mammal" is defined by but a few qualities that are abstract, whereas the class of "horse" is defined by more numerous qualities that are concrete.

The benefit to abstractions is that they lend the ability to create broad classes without detailed knowledge - and the drawback is exactly the same, in that there is a significant risk of inaccuracy in a broad classification system.

In a social sense, it is much easier for people to agree upon concrete concepts than abstract ones. If the class is defined by characteristics that can be perceived through the senses, than all it takes to form an agreement is for both persons to experience the same sensations at the same time - to hear the same sound or see the same object creates an instant agreement if their perceptions are not filtered to ignore the specific quality in question.

But it is much more difficult to agree on abstract concepts because there can be no sensation that both may experience at once. And so each person has a highly idiosyncratic understanding of abstract concepts such as love, faith, belief, or justice. Two people may love the same object, but each loves it in their own way and for their own reason.

The means by which we negotiate concepts with one another is through the vehicle of language. But words are an imperfect medium for the communication of thoughts. One person creates a word to symbolize a concept, and another person may adopt the word but applies it to their own understanding. The word does not convey the essence of the concept, but only its name. It becomes part of their common vocabulary when their concepts are roughly the same, but conceptions are never perfectly the same. Even an extended discussion in which the granular details of the concept are explored fails to yield a unity of thought.

And even within our own conceptions, flaws arise because of the idiosyncrasies of things. Many people consider the whale to be a fish because it resides in the ocean, but others recognize that its physical properties qualify it as a mammal. And to make matters worse we are careless with language: we may refer to a whale as a fish, even though we know it to be a mammal, because it has certain properties that are germane to our current line of thinking in which the similarities take precedence over the differences.

Concepts tend to be automatically formed about the most familiar things of life - those that are encountered frequently, or have the greatest importance to our interests. However, if left unattended the formation of these concepts is often erroneous.

One is better served by being more careful about developing accurate concepts of the things that most matter - which requires careful attention and intentional consideration of them. There is also the danger of abstracting too much - such that our concepts become too far removed from reality - which is the reason that practical experience must be employed to reinforce and validate purely philosophical explorations.

Atkinson highly recommends the practice of making a note, physical or mental, of anything you encounter that you do not understand and later making a more thorough investigation of that thing. A student who takes the time to consult a dictionary while reading has a better understanding of a subject than one who simply guesses the meaning of a word he does not comprehend, and who thereby distorts his understanding of things.

Dictionaries and encyclopedias, and a good library of general reference books, are requisite to developing a sound and accurate understanding of the world. A person would be well served if he were to devote half an hour every evening to seeking more knowledge and more accurate knowledge of the things he encounters in daily life.

He tells an anecdote about a man who purchased a set of encyclopedias and made a habit of reading an article every evening. It is said that in a year he made a noticeable advance in his general knowledge and habits of thought, and within five years was looked upon by his colleagues as a man with a remarkably large field of general information and of extraordinary intelligence. It is, he reckons, a significant return on a relatively small amount of time that might have been wasted on idle pursuits.