Since karma isn't the only thing that determines what happens to you, what are the other aspects?
I remember hearing a dharma talk where someone explained that there were like eight things that determined what happened to you and that karma was only one. Is there a sutta referencing this and what are those other things?
Yes, the following discourse is what you are looking for:
On one occasion the Blessed One was dwelling near Rajagaha in the Bamboo Grove Monastery, the Squirrel's Feeding Place. There Moliyasivaka the wanderer went to the Blessed One and, on arrival, exchanged courteous greetings with him. After an exchange of friendly greetings & courtesies, he sat to one side. As he was sitting there, he said to the Blessed One, "Master Gotama, there are some brahmans & contemplatives who are of this doctrine, this view: Whatever an individual feels — pleasure, pain, neither-pleasure-nor-pain — is entirely caused by what was done before. Now what does Master Gotama say to that?"
[The Buddha:] "There are cases where some feelings arise based on bile. You yourself should know how some feelings arise based on bile. Even the world is agreed on how some feelings arise based on bile. So any brahmans & contemplatives who are of the doctrine & view that whatever an individual feels — pleasure, pain, neither-pleasure-nor-pain — is entirely caused by what was done before — slip past what they themselves know, slip past what is agreed on by the world. Therefore I say that those brahmans & contemplatives are wrong."
"There are cases where some feelings arise based on phlegm... based on internal winds... based on a combination of bodily humors... from the change of the seasons... from uneven care of the body... from harsh treatment... from the result of kamma. You yourself should know how some feelings arise from the result of kamma. Even the world is agreed on how some feelings arise from the result of kamma. So any brahmans & contemplatives who are of the doctrine & view that whatever an individual feels — pleasure, pain, neither pleasure-nor-pain — is entirely caused by what was done before — slip past what they themselves know, slip past what is agreed on by the world. Therefore I say that those brahmans & contemplatives are wrong."
When this was said, Moliyasivaka the wanderer said to the Blessed One: "Magnificent, lord! Magnificent! Just as if he were to place upright what was overturned, to reveal what was hidden, to point out the way to one who was lost, or to carry a lamp into the dark so that those with eyes could see forms, in the same way has the Blessed One — through many lines of reasoning — made the Dhamma clear. I go to the Blessed One for refuge, to the Dhamma, & to the community of monks. May the Blessed One remember me as a lay follower who has gone for refuge from this day forward, for life."
-SN 36.21, To Sivaka
There are five "niyama dhamma". Kamma (karma) is only one out the five.
Utu niyaama (utu stands for seasons/weather) - As applied it means if a person dies from a natural disaster it is not purely due to karma - but it is due to the nature/ seasons. Things that are brought about as results of seasons and weather are not due to karma.
Beeja nyaama (beeja stands for seeds) - As applied seeds of a kind of plant species can produce that kind of trees. If your parents are black in color, you are going to be black, like that. Among humans or animals if karma is very powerful karma can override this to a certain level.
Kamma nyaama - What you receive due to good and bad you have done in this life and previus lives.
dhamma nyaama - This explains that growing old and things are not due to karma.
chitta nyaama (chiththa stands for mind) - thing that happen due to the way you think.
"Nigantanathaputta" who lived in Lord Buddha's time explained his theories only based on karma. As everything is 100 percent karma.
Buddhism does not say everything is due to karma. It describes karma and let people do good and to avoid bad.
Cosmic order is decided by the 5 Niyama Dhammas. All this together are the driving force behind the universe in which Karma is just one factor.
