Why did J. S. Mill believe a science of human nature was possible? What would characterize such a science in its early stages of development? In its later stages? Include in your answer a discussion of primary and secondary laws.
John Stuart Mill was an English philosopher of the nineteenth century and son of James Mill, who was also a prominent English philosopher. He has been called the most influential English-speaking philosopher of nineteenth century. He was one of the most influential thinkers in the history of liberalism.
Other philosophers during the time of J. S. Mill were focused on the natural science and the creation of mental science. However, it was J. S. Mill who contributed his work towards the science of human nature. In his analysis, he said that all that works on principles or laws are subject to science.
He rejected the ideas of other philosophers who believed that human emotions, thoughts and actions are not subject to scientific investigation. According to him, anything that is governed by natural laws is subjective to science. He claimed that human behavior also runs with some natural laws and principle, and hence, the science of human nature is also possible.
J. S. Mill explained the development of sciences from its early stage to the later stage. According to him, the sciences which are more difficult to predict at the early stage can become an exact science when the law governed for that science becomes sufficient.
He gave the example of astronomy. Astronomy was first considered as an inexact science at its early stage. However, once the laws governing the motions of astronomical bodies became sufficient, it became the exact science. Thus, he differentiated two stages as follows:
1. At the early stage, science stays as inexact as the laws governed are very difficult to predict, partially predicted or impossible to predict.
2. At the later stage, when the laws become sufficient, the inexact science becomes the exact science.
J. S. Mill divided the laws of science into two types namely, primary and secondary. Primary laws are those whose phenomenon are observed and predicted precisely, while secondary laws are those which make the prediction impossible. Though causes of events are unknown, primary laws gives information about the effects, but the secondary laws make the predictions more problematic.