| General Introduction. BY PREST. PORTER, | [v] |
| On The Physical Basis of Life. PROF. T. H. HUXLEY, | [1] |
| Correlation of Vital and Physical Forces. PROF. G. F. BARKER, M.D., | [37] |
| As Regards Protoplasm—Reply to Huxley. JAMES HUTCHISON STIRLING, | [73] |
| On The Hypothesis of Evolution. PROF. E. D. COPE, | [145] |
| Scientific Addresses. | |
| On the Methods and Tendencies of Physical Investigation, | [219] |
| On Haze and Dust, | [234] |
| On the Scientific Use of the Imagination, | [247] |
| PROF. JOHN TYNDALL, LL.D., F.R.S., | [217] |
INTRODUCTION TO THE NEW EDITION OF HALF HOURS WITH MODERN SCIENTISTS.
The title of this Series of Essays—Half Hours with Modern Scientists—suggests a variety of thoughts, some of which may not be inappropriate for a brief introduction to a new edition. Scientist is a modern appellation which has been specially selected to designate a devotee to one or more branches of physical science. Strictly interpreted it might properly be applied to the student of any department of knowledge when prosecuted in a scientific method, but for convenience it is limited to the student of some branch of physics. It is not thereby conceded that nature, i.e., physical or material nature is any more legitimately or exclusively the field for scientific enquiries than spirit, or that whether the objects of science are material or spiritual, the assumptions and processes of science themselves should not be subjected to scientific analysis and justification. There are so-called philosophers who adopt both these conclusions. There are those who reason and dogmatize as though nature were synonymous with matter, or as though spirit, if there be such an essence, must be conceived and explained after the principles and analogies of matter;—others assume that a science of scientific method can be nothing better than the mist or moonshine which they vilify by the name of metaphysics. But unfortunately for such opinions the fact is constantly forced upon the attention of scientists of every description, that the agent by which they examine matter is more than matter, and that this agent, whatever be its substance, asserts its prerogatives to determine the conceptions which the scientist forms of matter as well as to the methods by which he investigates material properties. Even the positivist philosopher who not only denounces metaphysics as illegitimate, but also contends that the metaphysical era of human inquiry, has in the development of scientific progress been outgrown like the measles, which is experienced but once in a life-time; finds when his positivist theory is brought to the test that positivism itself in its very problem and its solutions, is but the last adopted metaphysical theory of science.
We also notice that it is very difficult, if not impossible, for the inquisitive scientist to limit himself strictly to the object-matter of his own chosen field, and not to enquire more or less earnestly—not infrequently to dogmatize more or less positively—respecting the results of other sciences and even respecting the foundations and processes of scientific inquiry itself. Thus Mr. Huxley in the first Essay of this Series on The Physical Basis of Life, leaves the discussion of his appropriate theme in order to deliver sundry very positive and pronounced assertions respecting the “limits of philosophical inquiry,” and quotes with manifest satisfaction a dictum of David Hume that is sufficiently dogmatic and positive, as to what these limits are. In more than one of his Lay sermons, he rushes headlong into the most pronounced assertions in respect to the nature of matter and of spirit. The eloquent Tyndall, in No. 5, expounds at length The Methods and Tendencies of Physical Investigation and discourses eloquently, if occasionally somewhat poetically, of The Scientific use of the Imagination. But Messrs. Huxley and Tyndall are eminent examples of scientists who are severely and successfully devoted respectively to physiology and the higher physics. No one will contend that they have not faithfully cultivated their appropriate fields of inquiry. The fact that neither can be content to confine himself within his special field, forcibly illustrates the tendency of every modern science to concern itself with its relations to its neighbors, and the unresistible necessity which forces the most rigid physicist to become a metaphysician in spite of himself. So much for the appellation “Scientists.”
“Half Hours” suggests the very natural inquiry—What can a scientist communicate in half an hour, especially to a reader who may be ignorant of the elements of the science which he would expound? Does not the phrase Half Hours with Modern Scientists stultify itself and suggest the folly of any attempt to treat of science with effect in a series of essays? In reply we would ask the attention of the reader to the following considerations.
The tendency is universal among the scientific men of all nations, to present the principles of science in such brief summaries or statements as may bring them within the reach of common readers. The tendency indicates that there is a large body of readers who are so far instructed in the elements of science as to be able to understand these summaries. In England, Germany, France and this country such brief essays are abundant, either in the form of contributions to popular and scientific journals, or in that of popular lectures, or in that of brief manuals, or of monographs on separate topics; especially such topics as are novel, or are interesting to the public for their theoretic brilliancy, or their applications to industry and art.
These essays need not be and they are not always superficial, because they are brief. They often are the more profound on account of their conciseness, as when they contain a condensed summary of the main principles of the art or science in question, or a brief history of the successive experiments which have issued in some brilliant discovery. These essays are very generally read, even though they are both concise and profound. But they could not be read even though they were less profound than they are, were there not provided a numerous company of readers who are sufficiently instructed in science to appreciate them. That such a body of readers exists in the countries referred to, is easily explained by the existence of public schools and schools of science and technology, by the enormous extension of the knowledge of machinery, engineering, mining, dyeing, etc., etc., all of which imply a more or less distinct recognition of scientific principles and stimulate the curiosity in regard to scientific truth. Popular lectures also, illustrated by experiments, have been repeated before thousands of excited listeners, and the eager and inventive minds of multitudes of ingenious youths have been trained by this distribution of science, to the capacity to comprehend the compact and pointed scientific essay, even though it taxes the attention and suspends the breath for a half-hour by its closeness and severity.
The fact is also worthy of notice, that many of the ablest scientists of our times have made a special study of the art of expounding and presenting scientific truth. Some of them have schooled themselves to that lucid and orderly method by which a science seems to spring into being a second time, under the creative hand of its skilful expositor. Others have made a special study of philosophic diction. Others have learned how to adorn scientific truth with the embellishments of an affluent imagination. Some of the ablest writers of our time are found among the devotees of physical science. That a few scientific writers and lecturers may have exemplified some of the most offensive features of the demagogue and the sophist cannot be denied, but we may not forget that many have attained to the consummate skill of the accomplished essayist and impressive and eloquent orator.
One advantage cannot be denied of this now popular and established method of setting forth scientific truth, viz., that it prescribes a convenient method of bringing into contrast the arguments for and against any disputed position in science. If materialism can furnish its ready advocate with a convenient vehicle for its ready diffusion, the antagonist theory can avail itself of a similar vehicle for the communication of the decisive and pungent reply. The one is certain to call forth the other, and if the two are present side by side in the same series, so much the better is it for the truth and so much the worse for the error. The teacher before his class, the lecturer in the presence of his audience, has the argument usually to himself; he allows few questionings and admits no reply. An erroneous theory may entrench itself within a folio against arguments which would annihilate its positions if these were condensed in a tract.