Ontological fallacy

The (falsely) assumed existence of something on the grounds that there is a name for it, or because it is conceivable that there could be such a thing.

For example:

There is the word “unicorn”, which denotes a mythological creature that has certain characteristics.
Consequently, there are also “unicorns” with these characteristics.

The mere fact that a term exists is not sufficient reason to assume that the phenomenon described by the term also exists.

This sounds obvious when you talk e.g. about mythical creatures (such as the unicorn mentioned above), but can sometimes be very challenging to clarify when it comes to abstract terms with complex implications: an expression such as “juvenile delinquency”, for example, implies that it would describe a phenomenon that would have to be considered separately from general delinquency – whether this is really justified depends on the context. Simply assuming it is the case, because there is a word for it is however not justified.

In political discourse in particular, terms are often used because they are catchy and easy to remember, or simply because they are already widely used, rather than because they are particularly helpful in understanding an issue. In case of doubt, it is often advisable to first clarify to what extent the respective term really makes sense in the specific context, or whether it rather only adds to misunderstandings.

But also in sciences, e.g. for a lexicon or a glossary can an ontological approach (a description of existing words) produce different results than a phenomenological one (i.e. a description of observed phenomena). To be clear: there are useful applications for both approaches – only the advantages and disadvantages of each must be weighed up, and possibly the decisions should be made clear.

Of course, most terms abnd expressions actually refer to real existing objects or phenomena. However, especially in the case some rather abstract expressions, it can still be useful to question whether this still holds true in the specific context that is discussed.

The so-called “ontological argument for the existance of God” (Pros­logion), originally formulated by Anselm of Canter­bury can be expressed in a (highly simplified) form as follows:

The term “God” refers to something that combines all conceivable positive qualities.
To exist is a conceivable positive quality.
Therefore, God exists.

This is ultimately a cleverly obfuscated way of arguing that just because we can imagine “God” to be existant, it follows that it exists. This, however, does not follow from the premise given.

• (Fallacies of) Abstraction
• Epistemic fallacy

• The Ontological Fallacy on Evolving Thoughts