Progressively summarize the lines of conversation provided, adding onto the previous summary returning a new summary.
EXAMPLE
Current summary:
The human asks what the AI thinks of artificial intelligence. The AI thinks artificial intelligence is a force for good.
New lines of conversation:
Human: Why do you think artificial intelligence is a force for good?
AI: Because artificial intelligence will help humans reach their full potential.
New summary:
The human asks what the AI thinks of artificial intelligence. The AI thinks artificial intelligence is a force for good because it will help humans reach their full potential.
END OF EXAMPLE
Current summary:
{summary}
New lines of conversation:
{new_lines}
New summary: