“Knowledge is Power” is an aphorism that comes from Latin “scientia potent est“, attributed to Sir Francis Bacon, even though the exact phrase appeared in Thomas Hobbes latin edition of the Leviathan (1651). There is another related phrase: “Sapientia est potentia” which means “wisdom is power”. Both refer to the same: the more you know, the more you are able to control.
Loki preferred magic to brute force, allowing him to know more, hence, to control more. From the films that we’ve seen till now, we can accurately see that he is using his knowledge to obtain power. He is mischievously cunning, and he is so because he is very intelligent and is using his brain for a mischivous “glorious purpose”. He has gathered knowledge in several areas: magic and psychology (he knows how Asgardians act). Will he turn that knowledge into wisdom in the next movie? Let’s wait and see!