Theory: Shardblades and Shardplate are the physical aspect of Odium and Honor.
Points in favor:
1) The header for Chapter 57 from Hero of Ages reads as follows:
Assuming that all Shards function somewhat the same, this would mean that Honor and Odium both have a physical, spiritual and cognitive aspect. Looking at Roshar from what we know, we've seen evidence of both the cognitive aspects. We have seen evidence of the spiritual aspects in stormlight and the unknown energy that powers Voidbinding. However, there has been no example of a physical aspect. Looking again at Ruin and Preservation, the physical aspect was something that was physically present in the world that gave great power to people. Taking atium as example, it does not follow natural laws. Both of these statements seem to apply to Shardplate and Shardblades.
I have come to see that each power has three aspects: a physical one, which can be seen in the creations made by Ruin and Preservation; a spiritual one in the unseen energy that permeates all of the world; and a cognitive one in the minds that controlled that energy.
There is more to this. Much more that even I do not yet comprehend.
2) Syl, an honorspren, seems to have an issue with Shardblades. Syl also has a very dramatic response to the name of Odium. We do not have a direct quote of her disliking Shardplate, however. So what could be the difference between Plate and Blade? People tend to lump them together, but Plate seems to function very differently than Blades do. In fact, while Blades work on humans, I put forth that their intended purpose was always to attack creatures made of stone. This is why Blades work so well on stone and inanimate objects, but only kill people. On this note, the eyes burning out effect of Blades seems to be more in line with Odium than Honor.
3) The Oathpact. Part of my theory contends that the Oathpact was an agreement between Honor and Odium. Odium would be able to send Voidbringers to Roshar, conquering humanity for reasons unknown. Honor would be able to keep 10 chosen Heralds alive to lead mankind against the Voidbringers. However, Odium would get the chance to break the will of the Heralds after each Desolation, and Honor would gain the use of Odium's physical aspect to arm humanity against the Voidbringers.
So that's the theory. Shardblades are the physical element of Odium's power, Shardplate is the physical element of Honor's. Discuss!
Edited by Vortaan, 16 January 2012 - 09:05 PM.