What's the plural form of illogicalness? Here's the word you're looking for.
Answer
The noun illogicalness can be countable or uncountable.
In more general, commonly used, contexts, the plural form will also be illogicalness.
However, in more specific contexts, the plural form can also be illogicalnesses e.g. in reference to various types of illogicalnesses
or a collection of illogicalnesses.