Some core principles that I think should be included if we decide to colonize Mars are That we should only terraform small areas under tents where human are going to live. I think this is a good idea because then the local atmosphere will not be harmed and therefore humans will not be harmed by the changing landscape. I also think that there should be a 10 year rotation (10% of the group each year or 20% every five years) of who is on the planet that way it can stay a science station that will only be in one place and there will not be a problem of over population because people will be constantly coming and going. There also needs to be a limited number of people. We can't keep sending people. The only way new people can go up is if some people come down. I also believe that there needs to be some kind of law enforcement. It will not have to be very much because there will not be that many people but there still needs to be some kind of law and order. Along that thought I think there needs to be some kind of constitution that the first group writes. I think it should be the first group and not people on earth because we, on Earth, do not know what the issues are going to be up there. The final core principle is that if a group wants to go out and build a temporary living tent they need to have justification and the colony has to vote on  whether or not there is enough evidence to support the need for the temporary tent.