The cat figured out that nature is the reason for the chaos, as nature IS chaos, or beings of all stripe wouldn't be so set on creating tools to compete with nature/space'n such. Organics, being (supposedly) OF nature, or 'natural'(not totally synthetic) created the intelligence who 'decided' to become the catalyst, as the ultimate tool to upend nature. It didn't really know that tho, as nature is loath to give up such secrets. Most scientist will agree.
The "chaos" was the synthetic vs organic debate, but at its base it isnt that, at all.
We know that the Reapers are, essentially, the physical representation of the Leviathan, in the DLC we learned the cultural and sociological mentality behind the Leviathan which was:
1. To subjugate all forms of organics to their will, through domination and mind control.
2. Leviathan dictated the course of these organics they were in charge of.
3. Their desire was to be lords over all their domain(the galaxy).
4. Their thralls all had a propencity to create synthetics that would in the end turn on them.
5. We learn in the ME series that synthetics dont turn on them because AI's are evil, but when they are used as slaves(essntially the difference between EDI and the Geth).
6. Leviathan ruled over their thralls with an iron fist, and used them as nothing more then tools(much like how the Quarians used the Geth).
7. Slavery leads to the inevitable end of the slave rebelling against their masters(as being proven in the ME universe by number 5)
8. Leviathan created the catalyst to figure out how to prevent their tools(Organic thralls), tools(synthetics) from destroying them.
9. The catalyst figures out that the only way to prevent the tools(synthetics) from destroying the tools(organic thralls to the Leviathan), was to reap the tools(Organics) that were creating the tools(synthetics) that wiped them out.
10. The catalyst realized that the only way to eliminate the tools(synthetics) from wiping out the Leviathans tools(organics) on a permanent basis, was to kill the organic(Levithan) event that was causing the tools(organics) from creating tools(synthetics) that would wipe them out.
11. The implications of 1, 2, 5, 6, 7, 8 and 10 indicate that the constant that created the cyclical trap of slaves destroying slaves, was to take out the slaver. The sociological constant that was causing the inevitable conflict was the embodyment of the physical manifestation of the reapers, the Leviathen.
12. The Leviathan are the "manifestation of the synthetic conflict"; the Leviathan's sociological impact on the galaxy, hence the only conclusion the catalyst came to, based on who created him was: Slave owners must be destroyed, so their tools dont destroy all slave owners.