The difficulty I see here, if you're not incorporating officially, is that you are assigning equity on future actions that neither of you know what the value wi

The difficulty I see here, if you're not incorporating officially, is that you are assigning equity on future actions that neither of you know what the value will be. What I mean by that is that say for instance he is given 60% equity with the idea in mind that he will do x amount of work. If three months down the road you think he's not doing x amount will you feel satisfied in giving this type of equity. I understand you do not want to be taken advantage of in this scenario as much of the benefit from a start up is gained in the equity but attempting to decide the equity decision so early on especially if neither of you is bringing something particularly unique and/or valuable to the equation is difficult. For that reason I agree with your partner in that you are probably better of waiting until later on to decide the equity split. As long as you have the general agreement that you are both in a partnership and are going to execute on whatever idea I believe the equity question will more or less work itself out as the work is completed.