Following the decline of scholasticism, logic was thought of as an affair of ideas by early modern philosophers such as Locke (1632-1704) and Hume (1711-1716).
Kant calls these forms Categories (in a somewhat different sense than employed by the Aristotelian logicians), of which he claims there are twelve: This conception of logic eventually developed into an extreme form of psychologism espoused in the nineteenth by Benno Erdmann and others.
Another view of logic espoused by Hegel and others of his school (such as Bradley, Bosanquet and others), was the 'Logic of the Pure Idea'.
In the modern period, Gottlob Frege said "Just as 'beautiful' points the way for aesthetics and 'good' for ethics, so do words like 'true' for logic", and went on characterise the distinctive task of logic "to discern the laws of truth".
These are that logic is the study of: (i) artificial formal structures, (ii) sound inference (e.g., Poinsot), (iii) tautologies (e.g., Watts), or (iv) general features of thought (e.g., Frege).