The traditional trolley problem asks a brutal question: if a runaway trolley will kill five strangers unless you pull a lever that redirects it toward one stranger, should you do it? In its classic form, it is a numbers problem wrapped in moral tension. Do you act and cause one death, or do nothing and allow five?
TST Ethics starts with its recipe:
Group ethics guides. Personal morality chooses. Act with good intent. Weigh the result. Adjust.
So let’s start with the group ethics layer. Clearly, killing one person is better than killing five. The next major question is whether letting something happen and doing something should be treated as ethically equal. In a binary decision like this, it is logical to treat doing and not doing as ethically equivalent choices. So, in the clean thought experiment, group ethics points toward pulling the lever and choosing the lesser harm.
But group ethics only guides. Personal morality still has to choose. Do you follow the group standard or not? In a purely hypothetical case, the guidance points toward following group ethics unless you have a reason not to. But that ambiguity is part of the problem.
In this case, unless you have a reason not to, TST Ethics asks you to follow group ethics and choose to kill less people.
However, reality is never as neat as philosophy class. What if the person on the side track is your child? Real decisions happen in messy reality, not sterile thought experiments. If someone chose to save their wife or child rather than five strangers, TST would not remove the moral burden, but it would recognize the human reality behind it.