Famous quotes containing the words spiritual and/or science:
“Doubtless, we are as slow to conceive of Paradise as of Heaven, of a perfect natural as of a perfect spiritual world. We see how past ages have loitered and erred. Is perhaps our generation free from irrationality and error? Have we perhaps reached now the summit of human wisdom, and need no more to look out for mental or physical improvement? Undoubtedly, we are never so visionary as to be prepared for what the next hour may bring forth.”
—Henry David Thoreau (18171862)
“We know only a single science, the science of history. One can look at history from two sides and divide it into the history of nature and the history of men. However, the two sides are not to be divided off; as long as men exist the history of nature and the history of men are mutually conditioned.”
—Karl Marx (18181883)