I can choose my thoughts -- my attitude -- like I choose my food: There is some food that is delicious and full of nutrients. (Obviously) Other food is delicious but basically empty calories. (Again: Obviously. But also: Sadly). There is pleasure in both. Some thoughts nurture and sustain me, others undermine and keep me in fear. There is pleasure in both. (The pleasure in the thoughts that undermine me is that it can be familiar - and thus comfortable - mental ground. Or it can allow me to indulge character defects I am unwilling to release.) I can choose which receive my focus. I may not always be able to choose which show up in a random moment, but I can certainly choose whether to regard or disregard it.
And I can influence how often "junk food" thoughts show up by changing my habitual actions. Again and again (and again, sigh) I encounter the great truth (maybe that should be Great Truth? or is that too grandiose?) that my actions change my insides; my thinking and attitude. I cannot change my thinking with my thinking.
The good news? I know how to change my thinking!