Imagine you have an ant in your hand. The ant does not know you are moving forward, nor you can crush it anytime. The ant is us human beings living on the Earth's surface. This course provides an introduction to learning how the Earth's dynamics works from the point of view of solid earth science. You will briefly learn the history of the Earth and its creations, and the consequent change in the environment. You will also learn the mechanism of an earthquake, a tsunami, and a volcanic eruption. You will feel the difference between time and space scales from your everyday life. (You can learn about fluid earth science in the class "Earth System B" held by Dr. Y. Miyamoto.)