I am fond of the ancient Greek concept of psyche — that we are a constantly changing self filled with thoughts and emotions as we react the world around us. Some philosophers took that idea and declared that most of our thoughts and all of our emotions are false — not illusions, they are real, just not a reflection of our true self. What seems to be very common in Buddhist thought is that the atman/soul is impermanent, and this is often wrongly taken to the conclusion that the atman/soul is an illusion. But even if Nagarjuna was correct that the self disappears upon physical death like a candle flame disappears when blown out, we cannot say that either was an illusion. Some ancient Greek philosophers made the same mistake of declaring that anything impermanent and change itself is illusion.