Daniel Dennett is a philosopher and cognitive scientist who works out of Tufts University. He is famous for, among other things, his outspoken atheism, his belief that the mind is entirely physically explained, and his belief that free will is compatible with a world determined by physical laws.
The most important idea he promotes is that the tools of philosophy are the tools of everyday life.
His latest book, Intuition Pumps and Other Tools for Thinking, chronicles tools, tricks, arguments, and other so-called "brain hacks" which philosophers use, but which are just as useful and applicable for anyone. Each of these things, alone, is not a big idea, but together they represent Dennett's biggest idea: Bringing high level thought down from the ivory tower.
Dennett, himself a hugely eminent philosopher, has long been a critic of the typical behaviors and interests of academic philosophers in general. In particular, he believes that the work of philosophers of mind and of cognitive scientists are not fundamentally distinct. In his estimation, the biggest questions about perception and consciousness remain open only because philosophers stop at the line of what they think is "in the realm of science" and scientist stop at what they think is "in the realm of philosophy".
That brings us back to the tools of philosophy, and why Dennett's idea that they are also tools for everyday life is such a big one. Basically, the tools that philosophers use exploit or employ the cognitive functions, idiosyncrasies failings, or skills of the human brain.
As a student of both cognitive science and of philosophy, Dennett simply asks: Why don't these tools apply wherever and whenever our experience is guided by the characteristics of the human brain?
It so happens that everywhere and always is where and when our experiences are guided by the characteristics of the human brain, so Dennett sees fit to apply them as broadly as possible.
For an example of these tools for thinking, check out the video below. Much more will be available in an upcoming Big Think Mentor workshop with Dennett.