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2026 - Volume 10 - Number 1

Knowledge Definition in Plato’s Theaetetus and Theory of Forms from the Lens of Unitarians

Olúkáyọ̀dé R. Adéṣuyì * ORCID: 0000-0002-4432-3210
Adekunle Ajasin University, Faculty of Arts, Department of Philosophy, Akungba-Akoko, NIGERIA

Open Journal for Studies in Philosophy, 2026, 10(1), 1-12 * https://doi.org/10.32591/coas.ojsp.1001.01001a
Received: 15 September 2025 ▪ Revised: 27 March 2026 ▪ Accepted: 21 April 2026

LICENCE: Creative Commons Attribution 4.0 International License.

ARTICLE (Full Text - PDF)

ABSTRACT:
The theory of Forms is both foundational and fundamental to Plato’s philosophy. Its importance makes many scholars argue that the theory is contained in virtually all dialogues of Plato. There are debates over the presence or otherwise of the theory in, especially, Theaetetus. While the Revisionists argue against the presence of the theory, the Unitarians argue for its presence. This paper recognizes the fact that the burden of proof is not on the Revisionists; hence, it does not take into cognizance their position. Its attention is rather on the Unitarians who strongly believe that the theory of Forms is contained and evident in all of Plato’s dialogues, including and especially, Theaetetus. While this paper argues for the presence of the theory of Forms in Theaetetus, it deviates from the argumentative route of the Unitarians. The intent of this paper is to show that the position of Unitarians is not acceptable. The paper concludes that the theory is not evidently apparent as argued by the Unitarians. Rather, its presence is hinted at and not fully blown.

KEY WORDS: Unitarians, Theaetetus, theory of Forms, presence.

CORRESPONDING AUTHOR:
Olúkáyọ̀dé R. Adéṣuyì, Adekunle Ajasin University, Faculty of Arts, Department of Philosophy, Akungba-Akoko, NIGERIA.

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