The characteristics of a true profession are not easily defined, but it may be assumed that they include the existence of a body of scientific principles as the foundation of the work and the exercise of some measure of control by the profession itself in regard to the qualifications of those who seek to enter its ranks. Taken together, these two characteristics may be said to mark off a true profession from a business or trade. The skilled craftsman or artisan may belong to a union which seeks to control the entrance to its ranks, but the difference between the member of the Amalgamated Society of Engineers and the member of the Institution of Mechanical Engineers is that the former belongs to a body chiefly concerned with the application of certain methods while the latter belongs to one which is concerned with those methods, not only in their application but also in their origin and development. It is recognised that there is a body of scientific knowledge underlying the practice of engineering, and the various professional institutions of engineers seek to extend this knowledge, while claiming also the right to ascertain the qualifications of those who desire to become members of their profession. The same is true in different ways with regard to the professions of law and medicine. It is to be noted also that within these professions the admitted member is on a footing of equality with all his colleagues save only so far as his professional skill and eminence entitle him to special consideration.
It will be seen at once that there are great difficulties to be overcome before teaching can be truly described as a profession. The diversity of the work is so great that it may be held that teaching is not one calling but a blend of many. It is difficult to find any common link between the university professor, the head master of a great public school, an instructor in physical training, and a kindergarten teacher. It is not easy to bring together the head master of a preparatory school, working in complete independence, and the head master of a public elementary school, dealing with pupils of about the same age as those in the preparatory school, but controlled and directed by an elected public authority under the general supervision of the Board of Education. Yet despite these apparent divergences of aim all teachers may be regarded as pursuing the same end. They are engaged in bringing to bear upon their pupils certain formal and purposeful