Read the following passage and answer the questions :
Every individual wants peace of mind. But it is hard to find a person who can say that he has attained such a state of mental equilibrium as will allow him to live a life of tranquillity. Peace of mind is a distant dream for all of us. What is the reason for this ? The reason is that people hanker after ideal peace, that is pure peace-a peace that is free from all kinds of non-peace items.
But this kind of absolute peace is not in nature’s store house. Let us take the analogy of rose. A rose is a very beautiful flower, but every stem has its thorns. Indeed, thorns are an integral part of the rose plant. A poet has rightly said that thorns serve as security guards for the flower. There must be non-peace items along with peaceful items. A peaceful mind is a very precious aspect of human nature and it too needs safety to maintain it’s sublime quality.
Fill in the blank :
Thorns are an .......... part of a rose plant .