[https://incarnateword.in/cwsa/12/nature-the-world-manifestation#p113]
He speaks of Cyclic nature of creation and not circular. What it means is that creation advances upto a point and when it is unable to go past a certain limit, it returns back and then picks up again. The return is because something was ignored, neglected, or left behind in the process of advancement. Hence, it returns to attend to that aspect and rectify it to the extent possible. However, each return and each advance is higher than the previous cycle. The cycles are the four yugas. Thus, each Satyuga is slightly higher than the previous Satyuga. Similarly, each Kaliyuga is a little better than the previous one.
A similar thing takes place as one moves from one life to another. The soul may advance, but the mind may not. Or the soul, mind and even the heart may advance, but life and the body are unable to keep peace. Hence, death intervenes and passing through the dissolution of the body, one starts the cycle of a new life. However, each birth is slightly better (in terms of consciousness), an advancement over the previous one.
Affectionately,
Alok Da
