We know many things wch we want words to express. Great things discoverable upon this principle. For want of considering wch divers men have run into sundry mistakes, endeavouring to set forth their knowledge by sounds; wch foundering them, they thought the defect was in their knowledge, while in truth it was in their language. Qu. Whether the sensations of sight arising from a man’s head be liker the sensations of touch proceeding from thence or from his legs? Or, Is it onely the constant & long association of ideas entirely different that makes me judge them the same? Wt I see is onely variety of colours & light. Wt I feel is hard or soft, hot or cold, rough or smooth, &c. Wt resemblance have these thoughts with those? A picture painted wth great variety of colours affects the touch in one uniform manner. I cannot therefore conclude that because I see 2, I shall feel 2; because I see angles or inequalities, I shall feel angles or inequalities. How therefore can I—before experience teaches me—know that the visible leggs are (because 2) connected wth the tangible ones, or the visible head (because one) connected wth the tangible head(231)? (M389) All things by us conceivable are— 1st, thoughts; 2ndly, powers to receive thoughts; 3rdly, powers to cause thoughts; neither of all wch can possibly exist in an inert, senseless thing. ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ An object wthout a glass may be seen under as great an angle as wth a glass. A glass therefore does not magnify the appearance by the angle. (M390) Absurd that men should know the soul by idea—ideas being inert, thoughtless. Hence Malbranch confuted(232). I saw gladness in his looks. I saw shame in his face. So I see figure or distance. Qu. Why things seen confusedly thro’ a convex glass are not magnify’d? Tho’ we should judge the horizontal moon to be more distant, why should we therefore judge her to be greater? What connexion betwixt the same angle, further distant, and greaterness? (M391) My doctrine affects the essences of the Corpuscularians. Perfect circles, &c. exist not without (for none can so exist, whether perfect or no), but in the mind. Lines thought divisible _ad infinitum_, because they are suppos’d to exist without. Also because they are thought the same when view’d by the naked eye, & wn view’d thro’ magnifying glasses. They who knew not glasses had not so fair a pretence for the divisibility _ad infinitum_. No idea of circle, &c. in abstract. Metaphysiques as capable of certainty as ethiques, but not so capable to be demonstrated in a geometrical way; because men see clearer & have not so many prejudices in ethiques. Visible ideas come into the mind very distinct. So do tangible ideas. Hence extension seen & felt. Sounds, tastes, &c. are more blended. Qu. Why not extension intromitted by the taste in conjunction with the smell—seeing tastes & smells are very distinct ideas?