In Tim O'Brien's story "The Things They Carried," intangible concepts and emotions are inextricably linked with the physical objects which symbolize them. This is true even in the case of something as basic and practical as the canned peaches in heavy syrup carried by Henry Dobbins, which are reminders of home and of physical comfort and enjoyment. The first physical objects O'Brien mentions are the letters from Martha that Jimmy Cross carried with him. Letters are clearly a prime example of physical objects which are valuable because of the thoughts and feelings they convey. This is true even though, in Jimmy Cross's case, the letters express simple friendship rather than the romantic love he wishes he could read into them.
The personal physical objects the troops carry are of vital importance because life has been reduced to a much more basic level in Vietnam than the one they experienced in America. It is as though they have had to save their most cherished possessions from a fire. Since most of what they have to carry is standard issue kit, and they are now soldiers in uniform with ranks and numbers, these few personal possessions serve as marks of individuality, as well as symbols of what matters most to them.
O'Brien explores the different ways in which one can carry something throughout the story. The soldiers carry diseases and themselves as well as physical objects and emotions. It is only towards the end of the story that O'Brien talks of the emotional burdens unconnected to physical symbols:
They carried all the emotional baggage of men who might die. Grief, terror, love, longing—these were intangibles, but the intangibles had their own mass and specific gravity, they had tangible weight. They carried shameful memories. They carried the common secret of cowardice barely restrained, the instinct to run or freeze or hide, and in many respects this was the heaviest burden of all, for it could never be put down, it required perfect balance and perfect posture.
The physical things the soldiers carry are, to some extent, reassurances against these dark thoughts that sometimes overwhelm them. O'Brien's argument throughout the text is that people in extreme situations, in which death is a regular occurrence, do whatever they can to adapt and survive. The survival strategies they adopt may seem absurd, crude, disrespectful, and counter-intuitive, but they do not have to make sense. After all, the situation itself does not make sense. A random collection of objects, and the memories and values they represent help the soldiers in coping with the emotional and psychological burdens they have to bear. This is why O'Brien places so much emphasis on his litanies of physical things.