The favour with which the first series of Professor Helmholtz’s
Lectures has been received would justify, if a justification were
needed, the publication of the present volume.
I have to express my acknowledgments to Professor G. Croome Robertson,
the editor, and to Messrs. Macmillan, the publishers of ‘Mind,’ for
permission to use a translation of the paper on the ‘Axioms of Modern
Geometry’ which appeared in that journal.
The article on ‘Academic Freedom in German Universities’ contains some
statements respecting the Universities of Oxford and Cambridge to which
exception has been taken. These statements were a fair representation
of the impression produced on the mind of a foreigner by a state of
things which no longer exists in those Universities, at least to the
same extent. The reform in the University system, which may be said to
date from the year 1854, has brought about so many alterations both in
the form and in the spirit of the regulations, that older members of
the University have been known to speak of the place as so changed that
they could scarcely recognise it. Hence, in respect of this article,
I have availed myself of the liberty granted by Professor Helmholtz,
and have altogether omitted some passages, and have slightly modified
others, which would convey an erroneous impression of the present
state of things. I have also on these points consulted members of the
University on whose judgment I think I can rely.
In other articles, where the matter is of prime importance, I have been
anxious faithfully to reproduce the original; nor have I in any such
cases allowed a regard for form to interfere with the plain duty of
exactly rendering the author’s meaning.