The team should have 3 or 5 members (not 4, its even and can also lead to 50/50). Get another founder or get a coach/advisor/friend who you both trust and that can make a rational decision when you 2 are of different opinions.
-- MV
In marriage, as in business, honesty and the ability to take another's perspective go a long way. Ideally, you've chosen a partner whose abilities and insights compliment your own and decisions can be made by the one most qualified to make them.
I would think twice about starting something with anyone who was immovable in their opinions. (and you'd know if they were or not pretty quickly) It may not be the first instinct of entrepreneurs, but there is a possibility that both parties are wrong! ;)
-jc
*edited for word choice