“Deep thinking” is usually used to describe a way of thinking rather than a single activity. It means you don’t just skim or react to information on the surface, but you pause and work through it at multiple levels. Some common aspects people include are:
• Depth of analysis – looking for underlying causes, connections and principles rather than just the immediate facts.
• Extended concentration – giving a question or idea your full attention for a long enough time that your mind can go beyond first impressions.
• Critical and reflective – questioning assumptions (including your own), testing different angles, and imagining consequences.
• Integrative – combining knowledge from different fields or experiences to form a more complete picture.
• Creative insight – not just breaking things down but also synthesising new ideas or solutions.
You can contrast “deep thinking” with “shallow” or “surface” thinking, where we jump to quick answers or accept information at face value. People cultivate deep thinking by reading slowly and actively, taking notes, asking “why” repeatedly, letting ideas incubate, and discussing them with others to test and refine their understanding.