Book excerpt: “Between the earliest and the latest of the works included here, we have two hundred and fifty years of vigorous and adventurous philosophizing,” Monroe Beardsley writes in his Introduction to this collection. “If the modern period can be only vaguely or arbitrarily bounded, it can at least be studied, and we can ask whether any dominant themes, overall patterns of movement, or notable achievements can be found within it. This question is one that is best asked by the reader after he has read, or read around in, these works.” This Modern Library Paperback Classic also includes a newly updated Bibliography.