220 THE STAR IN THE WEST HUME Hume , at heart a thoroughgoing agnostic and man of the world , saw the practical falsity of abstruse philosophy , the conclusions of which were at once dissipated by the “ feelings of our heart,” which re duced “ the profound philosopher to a mere plebeian .' He forcibly asserts , that ideas of primary qualities are attained by abstraction— " an opinion which if we examine it accurately , we shall find to be unintelligible , and even absurd .” He further agrees with Berkeley in stating that : “ An extension that is neither tangible nor visible , cannot possibly be conceived ,” and that , “ The mind has never anything present to it but the perceptions , and cannot possibly reach any experience of their connexion with objects ."' And again that the " ... universal and primary opinion of all men is soon destroyed by the slightest philosophy , which teaches us , that nothing can ever be present to the mind but an image or perception , and that the senses are only the inlets through which these images are conveyed , without being able to produce any immediate inter course between the mind and the object .”. However , the great unknown waste of this “ immediate inter course ” Hume bravely sets out to explore . As Berkeley had previously got hopelessly bogged in the swamps of God , so Hume , avoiding the shore line , set out on the same quest by way of the desert of Scepticism , without the chart of so divine a know ledge , but with the compass of a more certain direc tion ; nevertheless , soon losing his way in the arid 1 An Enquiry concerning Human Understanding , p . 163 . 2 Ibid . p . 161 .