Johann Hari opens by presenting research and reporting suggesting depression and anxiety often substantially reflect disconnection from genuine fundamental human needs — meaningful work, community connection, natural environment — rather than purely individual brain chemistry imbalance alone.

Why this disconnection framing matters:

• Conventional understanding has often emphasized purely individual brain chemistry explanations for depression and anxiety, while Hari's extensive reporting and research review suggests broader social and environmental disconnection factors deserve significant additional attention
• This framing doesn't necessarily deny biological factors entirely, but argues for substantially expanded attention to these social and environmental disconnection factors
• This opening establishes the book's foundational, somewhat contested thesis, motivating its subsequent detailed examination of specific disconnection factors

This opening establishes the book's foundational thesis regarding depression and anxiety's connection to disconnection from genuine human needs, presented as a significant complement to purely individual brain-chemistry explanations.