Hume hails philosophers primeval thoughts about the non-materiality and non-existence of the external world by a very strong proposition that external objects are only perceived to be existent when our senses perceive them. Other than that, Hume declares that the external objects do not have any relevance in their existence. He debates that when one observes and perceives a particular object say for example a chair, the chair is only existent for us till our senses perceive that the chair exists and their continued existence even after our senses are false. Through this, he declares that it is a tricky situation where does the belief arrive to support the senses to accept the objects as existent. He claims that it may be arriving from either perception or senses, reason or imagination.
That the belief does not derive from perceptions or senses or from reasoning, Hume says that there must be a different faculty which supports the belief in the existence of distinct objects. He argues that since perception alone cannot be depended upon to prove the existence of distinct objects, one finds causal correlation between the cause and effect that must be derived from causal reasoning. Hume argues that anything that is reasonable must only come from a proper basis of validity and not from the masses confounding on their perception of the existence of the external world. Thus, he eliminates reason as a source of support for the belief in the existence of distinct objects. Lastly, he is left with one instrument of imagination, to which he says that if perceptions and reason do not support the belief, imagination is seen to be supporting the belief in distinct objects.