Page:Popular Science Monthly Volume 3.djvu/759

Rh

NOW pass to the second part of my discourse. It is in reference to the methods of modern science—the caution to be observed in pursuing it, if we do not wish to pervert its end by too confident assertions and deductions.

It is a very common attempt, nowadays, for scientists to transcend the limits of their legitimate studies, and in doing this they run into speculations apparently the most unphilosophical, wild, and absurd; quitting the true basis of inductive philosophy, and building up the most curious theories on little else than assertion; speculating upon the merest analogy; adopting the curious views of some metaphysicians, as Edward von Hartmann; striving to work out speculative results by the inductive method of natural science.

And such an example as this is of great value to the reflective mind, teaching caution, and demonstrating the fact that, while the rules by which we are guided in scientific research are far in advance of those of ancient days, we must not conclude that they are perfect by any means. In our modern method of investigation how many conspicuous examples of deception we have had in pursuing even the best method of investigation! Take, for instance, the science of geology, from the time of Werner to the present day. While we always thought we had the true interpretation of the structural phenomena of the globe, as we progressed from year to year, yet how vastly different are our interpretations of the present day from what they were in the time of Werner! In chemistry, the same thing is true. How clearly were all things explained to the chemist of the last century by Phlogiston, which, in the present century, receive no credence, and chemical phenomena are now viewed in an entirely different light!

Lavoisier, in the latter part of the last century, elucidated the phenomena of respiration and the production of animal heat by one of the most beautiful theories, based, to all appearances, upon well-observed facts; yet, at the present day, more delicate observations, and the discovery of the want of balance between the inhaled oxygen and exhaled carbonic acid, subverted that beautiful theory, and we are left entirely without one. It is true we have collated a number of facts in regard to respiration, molecular changes in the tissues, etc., all of which are recognized as having something to do with animal heat; still it is acknowledged that we are incapable of giving any concrete expression to the phenomena of respiration and animal heat as Lavoisier did eighty or ninety years ago.