Psychology makes ideas of educational aims clearer. When one says that the aim of education is culture, or discipline, or efficiency, or happiness, or utility, or knowledge, or skill, or the perfection of all one's powers, or development, one's statements and probably one's thoughts, need definition. Different people, even amongst the clearest-headed of them, do not agree concerning just what culture is, or just what is useful. Psychology helps here by requiring us to put our notions of the aims of education into terms of the exact changes that education is to make, and by describing for us the changes which do actually occur in human beings.