+ + – J. Philos. 3: 469. Ag. 16, ’06. 1060w. (Review of v. 5.) Lit. D. 32: 362. Mr. 10, 06. 950w.

“Its philosophy may be admirable, but it is unintelligible to one not a trained metaphysician, and its style seems constantly on the verge of a lucidity which as constantly proves elusive.”

+ – Nation. 81: 508. D. 21, ’05. 120w. (Review of v. 4.)

“His work remains of high interest as a human document, and abounds in memorable sayings and incitements to quotations.”

+ + – Nation. 82: 81. Ja. 25, ’06. 850w. (Review of v. 3.)

“If it fails wholly to please us it must be because we are too weak to care for the truth, or too lazy to follow it. One can hardly fancy a work on natural science more clear or more logical.” Bliss Carman.

+ + N. Y. Times. 11: 45. Ja. 27, ’06. 3870w.

“The fundamental misconceptions that have been noticed in the former volumes stand out in this. Professor Santayana’s skeptical criticism of scientific method and progress has the advantage of a charming literary style.”

+ – Outlook. 82: 717. Mr. 24, ’06. 310w. (Review of v. 5.)

“It is a work nobly conceived and adequately executed.” John Dewey.