You're absolutely right. It is "the way that you act, think, and just generally live your life [that] determines what you are." And your basic principles, values and temperament need not change. But the world is going to change and the issues it presents to you are going to be constantly changing. Conservative solutions that worked in the 19th century may not be adequate to deal with 21st century problems.
I am not sure just what "conservative solutions" will be required that is different from the past. I remember a phrase that goes, There is nothing new under the sun.