Kā ateists, es būtu pirmais, kas norādītu, ka ir iespējams iedomāties fenomenus un lietas, kurām nav loģiski nepieciešamas eksistences. Šis bija Sokrātiskās metodes jautājums, ar mērķi noskaidrot priekšstatu cēloņus. Piemēram, var diezgan droši teikt, ka priekšstati par nāriņām cilvēka iztēlē korelē ar priekšstatu cilvēks+zivs, kentauri—cilvēks+zirgs utml.

Gorgias is the author of a lost work: On Nature or the Non-Existent. Rather than being one of his rhetorical works, it presented a theory of being that at the same time refuted and parodied the Eleatic thesis. [Eleatic thesis: everything is One and unchanging] The work developed a sceptical argument, which has been extracted from the sources and translated as below:

• Nothing exists;
• Even if something exists, nothing can be known about it; and
• Even if something can be known about it, knowledge about it can't be communicated to others.

The argument has largely been seen as an ironic refutation of Parmenides' thesis on Being. Gorgias set out to prove that it is as easy to demonstrate that being is one, unchanging and timeless as it is to prove that being has no existence at all.