For the tweet "Whether my glass is half empty or its half full. I'm just grateful I even have a glass and that there's something in it.\n #optimism 🤔", determine the author's emotional state. Choose the correct classification from: 3: very positive emotional state can be inferred, 2: moderately positive emotional state can be inferred, 1: slightly positive emotional state can be inferred, 0: neutral or mixed emotional state can be inferred, -1: slightly negative emotional state can be inferred, -2: moderately negative emotional state can be inferred, -3: very negative emotional state can be inferred.