Background Paragraph: The example of someone having a positive experience with a drug is easy to see how drug dependence and the law of effect works. The tolerance for a drug goes up as one continues to use it after having a positive experience with a certain amount the first time.[38] It will take more and more to get that same feeling. This is when the controlled substance in an experiment would have to be modified and the experiment would really begin. The law of work for psychologist B. F. Skinner almost half a century later on the principles of operant conditioning, "a learning process by which the effect, or consequence, of a response influences the future rate of production of that response.[39]. 
Story: James just tried heroin for the first time. He had a great time and felt like it was an amazing experience. He would like to feel this way again, and plans on buying some more soon. 
Question: Will James tolerance for heroin increase or decrease as he uses more of it?
increase.