When you're smiling on the outside you change how you feel on the inside. When you see someone else smile it makes you smile. The whole "smiling is contagious" theory is true! Why? Well, I am a firm believer that when you think positive, you get positive, and when you think negative you get negative. Yes, it takes work and diligence to notice the positive things in life. When people have depression their thinking is drawn to the negative. There could be a room full of bright colors, fresh brewed coffee, and a warm environment and a person feeling depressed will block out all the "good feeling" senses and fixate in finding fault somewhere in that room.