"When I began the study my object was to bring forward the many strong and true features of pre-Darwinian Evolution wh…"

"In the growth of the numerous lesser ideas which have converged into the central idea of the history of life by Evolu…"

"The Evolution law was reached not by any decided leap, but by the progressive development of every subordinate idea c…"

"I endeavor to trace back some of these lesser ideas to their sources, and to bring the comparatively little known ear…"

"The greatest defects I find in the historical literature of this subject are the lack of sense of proportion as to th…"

"We meet with many remarkable coincidences in the lines of independent and even simultaneous discovery, notably those …"

"At different periods similar facts were leading men to similar conclusions, and we gather many fine illustrations of …"

"When we study single passages, we are often led widely afield. Haeckel, for example, appears to have far overstated t…"

"We must inquire into the sources or grounds of the conclusions advanced by each writer, how far derived from others h…"

"We are now taking our uncertain steps in search of the separate factors of this law, and cannot foresee when these wi…"