Partner doesn't acknowledge my observations

This will be hard to explain but it is a pattern I have noticed over the years.   Here is an example from today.   We were looking at an area of the lawn we want to turn into a garden.   It faces south and on the right side there is a tree.  I have been watching this spot over months to see where the sun is.   It turns out the right 1/4 of it gets much less sun.   Today I explained this to him and he would not acknowledge my observation.   Instead, he started explaining the science of how that could not be.   Then he asked me to explain to him how my observation could be true given the science.   This same pattern has gone on for years.   A couple of years ago, in my apartment I had at the time, he explained why I could not have sun in a certain spot of my apt.   Ever.   Well as summer came on, that area got really bright.   He was wrong.   LOL.    Anyway, it's been so frustrating I ended up telling him to F*** off today.   I mean, if he can't acknowledge my observations there is no point in having a conversation.