Radhanath Swami
In order to have simplicity of mind one must have simplicity of life style, which means one must be detached from gain or loss, pleasure or pain, honor or dishonor, happiness or distress. One must simply be seeking purification of consciousness.
Bhaktisiddhanta Sarasvati Thakura
Vaisnavism is the other name of simplicity. The servants of the paramahamsa Vaishnavas are simple; therefore they are the best brahmanas.
Radhanath Swami
Simplicity means without duplicity. A simple person has no ulterior motives. He speaks honestly & politely to encourage others.