Stoic theory of signs

Stoic sign theory is an important doctrine of the early phase of semiotic research or reflection.

One crucial part of this doctrine is the statement that the sign unites three components:

1. material and respectively perceptible sign vehicle (for example sound or inscription)
2. meaning or lekton (what is thought or said)
   and
3. an external object.

Here we have a clear triadic pattern of the sign.

Stoic theory of the sign is an essential part of Stoic logic, a highly developed doctrine still worthy of study.

In opposition to making an intangible unit (lekton) part of the sign, the Epicurean philosophers proposed a dyadic model of the sign, in which only sensory impressions and material objects are recognized as status.