This week’s session of the Philosophy Community’s reading group is based on Hume’s Enquiry Concerning Human Understanding.

The essay is very interesting and makes some powerful points about the types of mental activities. Hume divides our mental processes into ideas and impressions. Ideas are drawn from the imagination or memory and are therefore less vivid and powerful. Impressions include our more lively perceptions and sensations such as vision or emotions. For example, an idea would be a gold mountain – a combination of the impressions of gold and a mountain aided by the imagination.

The point that I found most interesting in the essay was Hume’s expansion of the hierarchy of mental processes (the derivation of ideas from impressions) to its application on language.

Here, therefore, is a proposition, which not only seems, in itself, simple and intelligible; but, if a proper use were made of it, might render every dispute equally intelligible, and banish all that jargon, which has so long taken possession of metaphysical reasonings, and drawn disgrace upon them. All ideas, especially abstract ones, are naturally faint and obscure: the mind has but a slender hold of them: they are apt to be confounded with other resembling ideas; and when we have often employed any term, though without a distinct meaning, we are apt to imagine it has a determinate idea annexed to it. On the contrary, all impressions, that is, all sensations, either outward or inward, are strong and vivid: the limits between them are more exactly determined: nor is it easy to fall into any error or mistake with regard to them. When we entertain, therefore, any suspicion that a philosophical term is employed without any meaning or idea (as is but too frequent), we need but enquire, from what impression is that supposed idea derived? And if it be impossible to assign any, this will serve to confirm our suspicion. By bringing ideas into so clear a light we may reasonably hope to remove all dispute, which may arise, concerning their nature and reality.

A term or proposition can not be useful unless it is built upon an idea which we know to be, in turn, built upon an impression. If we feel that a philosophical term has no effective basis, a simple test for the originating impression can prove our question. Connecting the meanings behind words to falsifiable ideas could only result from the hierarchy he built earlier and gives him the powerful tool of validating disputable ideas.