These aspects were empowered by beings called the Titans. We know very little about them, though a Dwarf named Brann has been studying them.
Having personally met the Aspects of Life and Time, and knowing those who have communicated with the Dreamer, I can tell you that they are not mad.
This madness manifests fairly obviously visually and usually quickly. Deathwing went mad over ten thousand years ago and is wholly evil. The other Aspects have been sane and protecting the world ever since.
Malygos, the aspect of Magic, I might worry about a little bit. He nearly lost his whole flight and Deathwing had driven him insane for a short time.
His sanity was restored, but I believe that he now views mortal magic users as a threat to the stability of the planet. That might not end well.