Premeditation or Experimentation?

This morning Sam was in the bathroom and quiet. I checked in to see him playing with a sink full of water and a little red boat. I'm fine with that. Several minutes later he emerged from the lavatory with a nearly empty container of Gold Bond Powder. He gleefully ran about the house saying, "I wasted it! I wasted it!" While squirting out clouds of stinky powder. At first I was furious. His statement indicated he deliberately emptied that powder into a sink full of water, making more work for me. I try to keep a sense of humor in these situations, but premeditated meanness is not funny. After cooling down I wondered if he was just curious what would happen when he added a new ingredient to his mixture. He knows soap makes bubbles. Sometimes we play with flour on the table and he makes roads with his cars. I wonder if he was working on a little experiment. I set him at the table with a container of water and some little boats so I could keep an eye on my sneaky little scientist. I was still angry about the mess and his dance through the house, but will accept partial responsibility for leaving a mischievious four-year-old alone in the bathroom.