Page:Life of Sir William Petty 1623 – 1687.djvu/141

 a lecture; for here my executors, that must part with this, will be sure to be well convinced of the invention before they do part with their money.'

Sir William, devoted as he no doubt mainly was to science, and especially to mechanical science, would, however, have been no true child of the seventeenth century, if he had not also dabbled in theology, and he unfortunately regarded it as one of his strong points. His studies frequently wandered off into the realm of metaphysical inquiry, and the transition thence to the realm of religious speculation was easy. To think, meant with him as a rule to write also, on whatever subject happened to be occupying his mind at the moment; and theology had a fatal attraction for his pen. He was for a long time engaged on a treatise, entitled 'The Scale of Creatures.' 'The discourse,' he tells Sir Robert Southwell, 'was not vulgar, nor easy to be answered by the libertine scepticks; of whom the proudest cannot be certain but that there are powers above him, which can destroy him, as they do with the viler animals. 'Tis hard to say where this scale ends, either upwards or downwards, but it is certain that the proud coxcomb man is not the top of it: wherefore let us be sober and modest, and conforme to the general practise of good men, and the laws of our age and countrey, and carefully study the laws of nature, which are the laws of God.' ...

The object of his work is alluded to more fully in another letter to Sir Robert: —

'I am glad,' he says, 'Lord Chief Justice Hayle hath undertaken the work you mention [on the Origination of Mankind], but Galen, De Usu Partium, will not do it:  1. the point is to prove that the most admired piece in the world, which Galen takes to bee man, was made by designe and pre-conceived idea, which his Maker had of him before his production. 2. What shall we say to the flaws and many infirmities in ye said piece, man; and ye difficulty of helping either your soare