Facts:

* Planets orbit the Sun: We observe planets moving in predictable paths around the Sun. This is a direct observation.

* Orbits are elliptical: Kepler's laws of planetary motion, based on meticulous observations, prove that planetary orbits are not perfect circles, but slightly elliptical.

Inferences:

* Orbits lie in nearly the same plane: While we observe planets from our perspective on Earth, which is also orbiting the Sun, the relative inclinations of their orbits are small. This suggests they formed in a common disk, a flat structure.

* All planets revolve around the Sun in the same direction: We observe planets moving in the same direction relative to the Sun. This is consistent with the idea that they originated from the same rotating disk, and their motion reflects that initial rotation.

In summary: We observe the planets' orbits and their motion. Based on these observations, we infer that they formed from a flat, rotating disk, leading to their similar orbital plane and direction of revolution.