According to the provided text, what makes a person 'truly wise' in the context of human life?

The text from Chapter 47 emphasizes the preciousness of human birth and the importance of using it for spiritual attainment. It defines a person who is 'truly wise' as one who does not waste the priceless opportunity afforded by a human life. This wisdom is demonstrated by diligently working towards attaining self-knowledge before the 'fall of the body,' or death. The text contrasts this with foolish beings who, through their actions and ignorance, are destined to receive a body corresponding exactly to what they have earned, thereby continuing the cycle of birth and death.