Dreams There are many theories about dreams ; their causes and meanings . Many of these contain some truth , but none can be scientifically proved to contain the whole truth . One theory is that dreams are caused by something affecting your body : if your bed clothes become twisted round your neck , you might dream that you were being strangled . This would not in itself , however , explain why you dreamed you were being strangled by your best friend . In that case , there will be another person as well as the bed clothes . You may recently have had a quarrel with your friend , for example . In a dream , a friend may appear as an enemy , and this may turn out to be true . Perhaps , over a period of time , all sorts of tiny hints about the friend's true character have been stored up in the unconscious mind , and for the first time they add up in the dream . You may not be willing with your conscious mind to admit that someone you like is making jokes about you behind your back , but such knowledge can be stored up in the unconscious mind . Sigmond Freud was the first person to put forward the theory of dreams as wish-fulfilment . Everyone , according to Freud , has sub-conscious wishes and fears of which their possessor is not consciously aware . A middle-aged man , who never gives a thought to girls during the day , might have a dream in which he was a sort of James Bond with lots of glamorous girlfriends . on waking up he might be quite shocked at having such a dream , but perhaps because of his shyness he has covered up and long forgotten his secret anxiety about his lack of contact with the other sex . Freud took this theory to the point of saying that unless people were able to express their secret wishes and fears in the form of dreams , they would not be able to sleep , and that therefore dreams are essential to our health .