What am I putting first?

One day a philosophy professor brought a large glass jar and some beautiful river rocks to class with I’m. “Raise your hands when the jar is full,” he instructed his students, and he began putting the big rocks into the jar. Soon the lid would no longer fit, and all the students raised their hands to indicate the jar was full. The professor then pulled out a bag of smaller black and white pebbles and poured them into the jar. As the pebbles rolled down, they filled in the little gaps between the big river rocks. The students smiled and raised their hands. This time the jar was completely full. Then the professor produced a bag of sand and began pouring it into the jar. When the sand had filled the tiny gaps between the rocks and the pebbles he triumphantly placed the lid on the jar and asked his class if the jar was full. They all clapped and agreed, “Yes, it is full!” At that point, the professor opened the lid and slowly poured two cups of coffee into the jar. The coffee completely filled the tiniest gaps between the rocks, the pebbles, and the grains of sand. “Now, life is very much like this jar,” he said. The river rocks represent the most important things in life, such as your ethics, your family, your loved ones, your health. Even if you lost everything else, your life would still be full with these most important things in it. The pebbles are the things in our lives that are pretty important—but our happiness shouldn’t depend on them. Things like our job, house, car, etc. shouldn’t depend on them. Things like our job, house, car, etc. Finally, the sand represents everything else—the countless small, busy things in our lives. If we fill up our jar with sand first, then we won’t have any room for the river rocks or pebbles. If we fill our lives with just the small stuff or the busy stuff, we won’t have any room or time for the things that mean the most to us.” After a brief moment of silence one of the students asked, “Professor, what does the coffee represent?” “Ah, I’m glad you asked,” replied the professor. “It means that no matter how full your life is, there is always room for a cup of coffee with a friend.”