What Is the Transcendental Recognition?

Philosophers often use the adjective transcendental, for example, when they speak of the transcendental consciousness, the transcendental intersubjectivity and so on. I will explain this seemingly difficult technical term as plainly as possible.
The System of Cognition

Mysterious monism criticizes the dualism of modern philosophers. We must, however, overcome the horizon of dualism and monism and aim at pluralism consisting of dualism.