Consider the following premises. For all x_19, x_19 is a taxi driver. For all x_19, x_19 will go running or x_19 is a police officer. For all x_19, x_19 is not a carpenter. For all x_19, x_19 will not go running or x_19 is a doctor. There is at least one x_19 for which x_19 is a police officer if and only if x_19 is a carpenter. Can we infer the following from them? For all x_19, either x_19 is a doctor or x_19 is a taxi driver are not true.
 From the fact that for all x_19, x_19 will go running or x_19 is a police officer, and that for all x_19, x_19 will not go running or x_19 is a doctor we can infer that for all x_19, x_19 is a police officer or x_19 is a doctor. From the fact that there is at least one x_19 for which x_19 is a police officer if and only if x_19 is a carpenter, and that for all x_19, x_19 is not a carpenter we can infer that there is at least one x_19 for which x_19 is not a police officer. From the fact that for all x_19, x_19 is a police officer or x_19 is a doctor, and that there is at least one x_19 for which x_19 is not a police officer we can infer that there is at least one x_19 for which x_19 is a doctor. Finally, from the fact that there is at least one x_19 for which x_19 is a doctor, and that for all x_19, x_19 is a taxi driver we can infer that there is at least one x_19 for which x_19 is a doctor and x_19 is a taxi driver, which contradicts that For all x_19, either x_19 is a doctor or x_19 is a taxi driver are not true. Therefore, the answer is no.