Furnish yourselves with a rich variety of ideas; acquaint yourselves with things ancient and modern; things natural, civil, and religious; things domestic and national; things of your native land, and of foreign countries; things present, past, and future; and above all, be well acquainted with God and yourselves; learn animal nature, and the workings of your own spirits. Such general acquaintance with things will be of very great advantage.
The first benefit of it is this: it will assist the use of reason in all its following operations; it will teach you to judge of things aright; to argue justly, and methodise your thoughts with accuracy. When you shall find several things akin to each other, and several different from each other, agreeing in some part of their idea, and disagreeing in other parts, you will arrange your ideas in better order, you will be more easily led into a distich knowledge of things, and will obtain a rich store of proper thoughts and arguments upon all occasions. …
Another benefit is this: Such a large and general acquaintance with things will secure you from perpetual admirations and surprises, and guard you against that weakness of ignorant persons, who have never seen any thing beyond the confines of their own dwelling, and therefore they wonder at almost ever thing they see; every thing beyond the smoke of their own chimney, and reach of their own windows, is new and strange to them.
A third benefit of such a universal acquaintance with things is this: it will keep you from being too positive and dogmatical, from an excess of credulity and unbelief, that is, a readiness to believe, or to deny, every thing at first hearing; when you shall have often seen, that strange and uncommon things, which often seemed incredible, are found to be true: and things very commonly received have been found false.
Isaac Watts, Logic: The Right Use of Reason in the Inquiry After Truth, pg.69-71