Final answer:
The transformative power in Sonnet 29 is the power of love, which transforms the speaker's feelings of worthlessness into a sense of self-worth and contentment.
Step-by-step explanation:
The transformative power described in Sonnet 29 by William Shakespeare is the power of love. The speaker in the sonnet expresses feelings of despair and self-pity, feeling dejected and inadequate. However, the transformative power of love enters the sonnet in the form of thoughts of a beloved person, and suddenly, the speaker's perspective changes.
Through the power of love, the speaker's state of mind is transformed from feelings of worthlessness to a sense of self-worth and contentment. The negative thoughts and feelings are replaced by thoughts of the beloved, who becomes a source of solace and comfort. The speaker describes how the mere thought of the beloved's presence and love can transform his state of mind, making him feel rich and blessed despite the hardships he faces.
An example of this transformation can be seen in lines 12-14, where the speaker states, "For thy sweet love remembered such wealth brings / That then I scorn to change my state with kings." These lines highlight how the transformative power of love elevates the speaker's perspective, making him feel abundant and superior to even kings.