The perception that the Earth appears flat is primarily due to the limitations of human perception and the relatively small scale at which we experience the Earth's curvature in our everyday lives.
At a local or small-scale level, such as walking on a flat surface or observing a relatively small area of land, the curvature of the Earth is not easily noticeable. The Earth's curvature becomes more apparent over larger distances or when observing the Earth from a higher vantage point.
Another factor that contributes to the perception of a flat Earth is the lack of noticeable visual references that can demonstrate the curvature. In our daily experiences, the ground and horizon often appear flat due to the vast size of the Earth and the limited field of view available to us.
Additionally, the effects of atmospheric perspective and light bending can also play a role in making the Earth seem flat. The atmosphere acts as a lens, refracting light and causing distant objects to appear slightly elevated, which can create an illusion of a flat horizon.
However, it is important to note that scientific evidence, such as photographs taken from space, satellite imagery, and observations of phenomena such as the curvature of the horizon during ship navigation or the Earth's shadow on the Moon during a lunar eclipse, overwhelmingly support the conclusion that the Earth is indeed a spheroid with a slight bulge at the equator, rather than flat.