Is samsara real?

If there is afterlife and sentient beings revolving around life after life in 3 different realms, and there is cosmic law that liberates all living beings and actually is eager to do so, then beings must be given ability to observe and realize the truth about samsaric worlds. However all Buddhist text books(eg. DN16, 22) indicate that only after one reaches fourth jhana one is able to acquire special wisdom to penetrate the reality of revolve around. Moreover the 4th jhana is known very hard to reach unless so much of effort should be put on. I seriously doubt the theory of samsara. Can anyone point out any flaws in my understanding and show how samsara could be real?