Acharya Prashant explains that sickness is always external to one's true nature; it is always 'the other'. He clarifies that if someone else's sickness or behavior is bothering a person and making them restless, it indicates that the person has contracted that sickness and is now infected. The speaker emphasizes that while sickness originates from the outside, the moment it begins to disturb one's internal state, it becomes one's own disease. Therefore, the first step in addressing the world's sickness is to ensure one's own system remains free from infection, influence, and impact. He advises that while the nonsense of the world is worth studying, it must not be allowed to encroach upon the mind. To understand or deal with sickness effectively, one must maintain a distance, which he identifies as the essence of witnessing and realization. He concludes that one must maintain personal aloofness and purity before attempting to engage with, study, or fight the sickness found in others.