Reinout Willem van Bemmelen quotes:

As geology is essentially a historical science, the working method of the geologist resembles that of the historian. This makes the personality of the geologist of essential importance in the way he analyzes the past.

[In geology,] As in history, the material in hand remains silent if no questions are asked. The nature of these questions depends on the "school" to which the geologist belongs and on the objectivity of his investigations. Hans Cloos called this way of interrogation "the dialogue with the earth," "das Gesprach mit der Erde."

[The] subjective [historical] element in geologic studies accounts for two characteristic types that can be distinguished among geologists: one considering geology as a creative art, the other regarding geology as an exact science.

Geology differs from physics, chemistry, and biology in that the possibilities for experiment are limited.

Experiments in geology are far more difficult than in physics and chemistry because of the greater size of the objects, commonly outside our laboratories, up to the earth itself, and also because of the fact that the geologic time scale exceeds the human time scale by a million and more times. This difference in time allows only direct observations of the actual geologic processes, the mind having to imagine what could possibly have happened in the past.

Geology is part of that remarkable dynamic process of the human mind which is generally called science and to which man is driven by an inquisitive urge. By noticing relationships in the results of his observations, he attempts to order and to explain the infinite variety of phenomena that at first sight may appear to be chaotic. In the history of civilization this type of progressive scientist has been characterized by Prometheus stealing the heavenly fire, by Adam eating from the tree of knowledge, by the Faustian ache for wisdom.

In our lives we have known hell and heaven; the final balance, however, is that we helped pave the way to dynamic harmony in this earthly house. That, I believe, is the meaning of this live.

There is, however, no universal recipe for scientific advance. It is a matter of groping forward into terra incognita of the outer world by means of methods which should be adapted to the circumstances.

We will be able to depart this life with the quiet peace-giving notion, that we were permitted to contribute to the happiness of many who will live after us. In our long lives we endeavored to unfold the collective consciousness. In our lives we have known hell and heaven; the final balance, however, is that we helped pave the way to dynamic harmony in this earthly house. That, I believe, is the meaning of this live.