Matthew Sweet

Fear is one of the six basic universal emotions (the others are anger, disgust, happiness, sadness and surprise) and like all human emotions not easy to understand. Fear can be played upon, enjoyed, conquered. It is an obstacle to progress ("the only thing to fear is fear itself") and, as we stand at the kerb, it saves our lives every day. This series of The Essay brings you five essays on different aspects of fear.

Tonight writer and broadcaster Matthew Sweet uncovers the tragic history of The Little Albert Experiment, conducted by John B Watson, a 1920s psychologist who conditioned a toddler to recoil from a white rat and, eventually, any white fluffy object.

Producer Laura Thomas.