"...the degree of our transcendence is determined by
the scope of our inclusion."
Let's look more closely at the aperture concept. Throughout history, spiritual and consciousness descriptions have relied on allegory, metaphor, and analogy. We will do the same except that available comparative objects have been characterized by modern science in far greater detail than objects of yore. For spiritual or consciousness system descriptions, the thinkers in remote agricultural based societies might have, say, chosen animals such as wolves or owls as metaphorical symbols based on skilled knowledge of their overt behavior. However we know those creatures down to their DNA, and were they chosen today as spiritual or consciousness model descriptors, the animal metaphors, allegories, and analogies could be far richer than what was possible centuries ago. Thinkers in earlier periods drew from the knowledge and metaphors available in their day, so why shouldn't we do the same?
So rather than animals, let's take a look at two common objects: the telescope and the antenna. Both of these widely understood items capture and concentrate information. A reflector telescope has an aperture equal to the diameter of its mirror. Light gathered over the entire mirror surface is focused through the use of physics principles and captured for viewing and study. Energy from a large area is concentrated and organized for capture in a manageable small area.
The long Yagi antenna as commonly seen around the world on rooftops and towers adds additional interest in that its working aperture is much larger than the antenna's physical size. The telescope's aperture size is immediately evident as a physical measurement. But the Yagi antenna's aperture is not actually visible to us, at least in the visual spectrum. The notion is described qualitatively here:
The working aperture of a common Yagi antenna is much larger than the physical antenna itself (see page 13). An engineer can define that aperture and easily imagine it invisibly yet functionally surrounding the antenna. Placing other antennas or metal objects within that aperture - the "near field" - will definitely affect the antenna's function. The designer can modify the shape and size of the antenna's aperture by modifying the physical structure - a key analogical point. As with the antenna, we will imagine a virtual but functional aperture around ourselves and every other person. There are more detailed engineering descriptions of antenna aperture with pictorials and mathematics here. The latter reference doesn't specifically address the Yagi design but is a quantitative description of antenna aperture physics. Engineering schools around the world offer antenna design course work such as here. Antenna aperture is a widely known and studied phenomenon.
The antenna and telescope are structures designed for one exact function. Yet a compelling analogy suggests that a consciousness aperture surrounds each person (or any other sentient being) not unlike the aperture that surrounds any everyday antenna structure. In both cases we can't "see" it, but we know it's there and active. That consciousness aperture as it passes through time - sticking to three dimensional concepts - is one's own temporal aperture.