Today's L&L article goes over the arcane caster trio, but there is a string bias of opinion there
So for the sake of fairness, here is how everyone else views the Wizard
Sorcerers, hunted by the Wizards:
Any self-respecting Sorcerer will tell you that wizards are at best dangerous to themselves, at worse a dire threat to those around them (no sorcerer ever thought putting an owl's head on a bear's body was a good idea). Wizards think by reading some books and attending school for a few years they can bend the cosmic forces of the universe to their own amoral ends. Sorcerers know better. Like a bird flies naturally with its wings, a Sorcerer was born with the gift of magic and developes it over a lifetime, but even with such careful practice they are not so foolish to so quickly declare themselves masters of the arcane.
Wizards view the natural talent of Sorcers with scornful jealousy. They believe sorcerers must be controlled and studied so that whatever power they hold can be harnessed and put to 'better use' (by Wizards). Evil wizards have no compunction with capturing sorcerers, experimenting on them, and eventually harvesting their organs for magical potions and other items.
Warlocks, persecuted by the Wizards:
If wizards are jealous of sorcerers, they simply scoff at warlocks. Warlocks have found a means to access arcane magic different than wizards, and to the intolerant wizards anything not their way is the wrong way. Wizards look down on warlocks as meddlers, thieves, and dangerous renegades, they practice magic outside the institutions established by wizards. Some wizardly academies go so far as to seek out and horde the books that warlocks seek. There are some secrets, a wizard may tell you, that are better off kept secret... and that secret is only for wizards to know.