What is the essence of PhD?

When people get their PhD, very often, we think that they know everything about their field. The truth is they are not.

What is the essence of PhD?

When people get their PhD, very often, we think that they know everything about their field. The truth is they are not. In fact, their PhD contributes only a small piece of addition to the current knowledge in their field. If we think the current knowledge of a field as a circle, then a PhD contribution to this circle is like a small bump pushing the boundary of the circle (figure 1).

In figure 1, the current knowledge of a field is represented as a circle with black border. A small blue circle represents the knowledge we gain during our undergraduate study. Then, when we continue to master study (represented as a brown oval or ellipse), we gain more knowledge in our field with tendency toward a specific topic. Finally, when we pursue our PhD, we start to explore more knowledge in a specific topic within the knowledge domain (for example via literature review). Based on this exploration, we go deeper and research this specific topic until, finally, at the end of our PhD, we can add a small novel knowledge (for example new findings, new methods or new models) that pushes the boundary of the current knowledge. That is, our Phd contribution is merely a small addition of knowledge out of the total current knowledge.

Figure 1: The illustration of PhD contributions in their field of study.

The essence

The next question is that what the essence we get from our Phd is. We might think that we will become an expert in our field in a certain topic. This answer is not wrong, but it is not totally true.

The essence of PhD is that we obtain an ability to confidently embrace new problems that we have not seen before and to find the most effective and efficient approaches to solve the problems. This ability allows us to identify what the problems are, to explore various types of alternative solutions and to synthesise the most suitable solutions for the problems. In addition, we develop the mindset of continuous learning and gain some of the most important skills for life: reading and writing.

As conclusion, having PhD does not mean that we know everything or we are very smart. However, having Phd means that we are not afraid to face new problems and have an ability to find the solutions of the problems.


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