Bruno Latour was once asked him: "Do you believe in reality?" This text is an attempt to answer this question. Through case studies of scientists in the Amazon analyzing soil and in Pasteur's lab studying lactic acid, he shows the steps by which physical events become scientific knowlege.

Bruno Latour was once asked him: "Do you believe in reality?" This text is an attempt to answer this question. Through case studies of scientists in the Amazon analyzing soil and in Pasteur's lab studying lactic acid, he shows the steps by which physical events become scientific knowlege.