How to get him to understand

My son is going to be 4 on March 4. And he still refuses to share. the toys are all divided. the boys have toys in the livng room which include the play kitchen, Animals, 1 robot, Cars, truks, Tracters, tool bench, baseball center just small toys that everyone can play with.

Then in my oldest sons room, he has his fave toys like his  trains, his learning robot, legos, 1 guitar, play cell phones, remote control cars.

 In my youngest sons room he has 1 guitar, play on toys, riding toys, play cell phones, learning toys, train tent, cars truks. alot of the same sort of toys his brother has

  And in the hallway upstaris is my oldest sons race track, and the elmo tool bench which they both have to share.

 But any way my mom came over to give the boys a valentines day gift. Well my mom gave both boys a set of cookies, a bag of M&Ms, and each a toy. Haiden my oldest got a Backhoe Tracter he can take a part and put back together, it came with the tools to do so. And Logan got a ball.

 Well my rule in the house is whatever toy is in the living room every kid has to share, including kids i baysit for. What ever toy is in Haiden's room is his and only his and he doens't have to share those toys unless he has his friends over and they are upstairs.And whatever toy is in Logans room is Logans and only Logans. and whatever toys in the hallway upstairs is for both my kids only.

 Well this morning Haiden took the tracter you can take apart and put back together, Logan took the tools as Haiden was getting it. But before Haiden took it apart i told him he might not want to since he knows his brother will take it. he didn't listen and Logan kept taking parts away. Haiden got it together and walked away, logan went to get it to play and Haiden comes up to him and takes it saying no that is not a baby toy and you can't have it. I looked at him and said what is the rule, and he then said what toys in the living room is for everyone. The i said ok but he kept fighting. So i tell him to stop, and he goes on the couch, i then said Haiden get off the couch, this is mine. He goes but it's everybodys. I said no it is mine and matter of fact most of these toys down here, in your room, your brothers room are all mine. He said why, and i said i bught them, so they belong to me. He started screaming and yelling share. I then told him but i am just doing what you do to everyone who comes over and asked him if he liked it. He said no and it makes him mad. I then said so if it makes you mad, don't you think it makes mommy, daddy and everyone else mad when you don't share. He says no. So i then said to him so what do you  think Logan should play with. He then said Baby toys, so i took out the tool bench, all of Logans play phones that he got for xmas, the baseball thing, some smaller cars  that he got for xmas and his bday which only  came to 11 baby things and the rest was all matchbox cars, and toys haiden said is not baby toys. I said so do you think it is fair that Logan only gets 11 toys and you get everything. he said yes. I said ok then to make it fair lets take the rest of your toys out and leave just the same amount of  toys for you that Logan can have. He started screaming saying no. I said ok then we need to share.

 It is just so frustrating that Haiden thinks everything is his, and no one elses. Its like it is his way or the highway. How can i get him to understand not every thing is his, since no sooner than we had the converstation he went right back to saying this is mine not yours.