In this post, we give an argument for why time can be circular when the world is understood using only the mind.
We first define what a theory is. We define a theory to be a simplification of the phenomenal world. That is, because of the limitations of the human mind, we need to simplify what is happening and explain it with a theory. For example, when we use a pendulum to measure acceleration due to gravity, we don't care about the exact tensile strength of the thread of the pendulum; we just say that it doesn't stretch when the pendulum swings. We don't specify the size of the bob; we just say that it is small, and so on. We simplify each element of the experiment and then calculate the acceleration due to gravity.
Now, assume a theory that explains everything that is happening in the world. This theory will approximately tell us what is going to happen at any time into infinity, assuming time is infinite. Now, if we assume time to be linear, then this theory will also be infinitely long because time is infinite. But due to the limitations of the human mind, we cannot have an arbitrarily large theory, so we would have to divide time into measurable chunks. Thus Time would become circular if we were to have a theory to explain all events forever. That is, if the world is to be understood using only the mind, the limitations of the human mind would make time circular.