A human being: an ingenious assembly of portable plumbing. – Christopher Morley, Human Being

It is curious to note the old sea-margins of human thought! Each subsiding century reveals some new mystery; we build where monsters used to hide themselves. – Henry Wadsworth Longfellow, Kavanagh, 1849

I demand of you, and of the whole world, that you show me a generic character… by which to distinguish between Man and Ape. I myself most assuredly know of none. – Carl Linnaeus, 1788

Man is the only trained animal who expects his reward before he does his trick. – Robert Brault, rbrault.blogspot.com