All linear reasoning is circular.
1) The observation of arguing one set of axioms requires the expansion of these axioms in one direction through reason as we divide and multiply these axioms to further axioms.
2) The axioms progress away from the origin of the original axiom through further axioms; however this progression of the axioms, as an inversion of the unity of the original unified axiom into multiple axioms, effectively cycles back to the original axiom as a point of inversion where the following axioms exist if and only if there is an original axiom with this original axiom being a point of inversion.
3) The original axiom, as a premise point of inversion into other axioms, exists through the other axioms as inversive themselves; hence the line of reasoning directed away from this original point of inversion is directed to further inversion through the original axiom as the foundation of the other axioms. In these respects all axioms are circular through a linear expansion.
A simpler example of this would be a line as directed away from a 0d point towards a 0d point while the line itself is composed of infinite 0d points.