It is getting harder and harder to be good in a world where choices that once seemed straightforward are now moral quandaries.
Decisions like what to eat or which car to buy are connected to global issues.
Associate research professor at the Johns Hopkins Berman Institute of Bioethics Travis Rieder's new book Catastrophe Ethics: How to Choose Well in a World of Tough Choices offers a new set of ethical tools to deal with new challenges.
Rieder told RNZ's Afternoons most ethical thinking was designed in a world very different to the one we live in today.
As humans have evolved and become a more globally connected society, people face more moral questions in daily life.
"The new class of issues is what I call in the book 'puzzle of individual choice' in this time of massive, collective structural problems."
Rieder said it only arose when a person's "tiny little contribution" either harmed or benefited an injustice or justice.
Climate change was a main example, he said.
He spoke of a person needing to drive to work. The was nothing wrong with that, except that the person's car released greenhouse gases into the atmosphere, which paired with other greenhouse gases contributed to the rising temperature of the world and caused extreme weather events.
Consumerism was another issue - where people could choose to buy items from ethical companies and withdraw support from others.
But it was not always easy. Rieder said a lot of ethically sensible people would say people should not buy products if they discovered it supported slave labour on the other side of the world, but there was "a problem here".
"You and me and probably almost everyone else listening, we've all supported in slave labour practices, likely, because we're talking on computers and phones and other things that require ion batteries and those batteries require cobalt and most of the cobalt in the world is mined in the Democratic Republic of Congo under conditions that at least one writer, Siddharth Kara, has called modern day slavery."
Withdrawing from such technology was not realistic, so new tools were needed, Rieder said.
He said some people told him such issues were structural problems and it seemed like he was victim blaming.
"It would be nice if the answer was 'well, our brightest minds and governments are on this problem' and so you could just sit back and not worry about it because it's going to be solved at the structural level, but in so far as much of these problems are not actually being solved, it does sort of feel like we've got to do something.
"We've got to do our part. But then the question is: 'what is our part? What's good enough?'"
Rieder said people were likely to be "constantly berated" by moral consideration for their entire life and it was important people stopped thinking in black and white.
People could consider what they could to raise awareness about issues, vote for leaders whose policies they agreed with, give money to organisations making change and carve their own path forward, he said.